1 What has changed in GDB?
2 (Organized release by release)
4 *** Changes since GDB 7.4
8 ** The "maint set python print-stack on|off" is now deleted.
10 * GDBserver now supports stdio connections.
11 E.g. (gdb) target remote | ssh myhost gdbserver - hello
13 * The binary "gdbtui" can no longer be built or installed.
14 Use "gdb -tui" instead.
16 *** Changes in GDB 7.4
18 * GDB now handles ambiguous linespecs more consistently; the existing
19 FILE:LINE support has been expanded to other types of linespecs. A
20 breakpoint will now be set on all matching locations in all
21 inferiors, and locations will be added or removed according to
24 * GDB now allows you to skip uninteresting functions and files when
25 stepping with the "skip function" and "skip file" commands.
27 * GDB has two new commands: "set remote hardware-watchpoint-length-limit"
28 and "show remote hardware-watchpoint-length-limit". These allows to
29 set or show the maximum length limit (in bytes) of a remote
30 target hardware watchpoint.
32 This allows e.g. to use "unlimited" hardware watchpoints with the
33 gdbserver integrated in Valgrind version >= 3.7.0. Such Valgrind
34 watchpoints are slower than real hardware watchpoints but are
35 significantly faster than gdb software watchpoints.
39 ** The register_pretty_printer function in module gdb.printing now takes
40 an optional `replace' argument. If True, the new printer replaces any
43 ** The "maint set python print-stack on|off" command has been
44 deprecated and will be deleted in GDB 7.5.
45 A new command: "set python print-stack none|full|message" has
46 replaced it. Additionally, the default for "print-stack" is
47 now "message", which just prints the error message without
50 ** A prompt substitution hook (prompt_hook) is now available to the
53 ** A new Python module, gdb.prompt has been added to the GDB Python
54 modules library. This module provides functionality for
55 escape sequences in prompts (used by set/show
56 extended-prompt). These escape sequences are replaced by their
59 ** Python commands and convenience-functions located in
60 'data-directory'/python/gdb/command and
61 'data-directory'/python/gdb/function are now automatically loaded
64 ** Blocks now provide four new attributes. global_block and
65 static_block will return the global and static blocks
66 respectively. is_static and is_global are boolean attributes
67 that indicate if the block is one of those two types.
69 ** Symbols now provide the "type" attribute, the type of the symbol.
71 ** The "gdb.breakpoint" function has been deprecated in favor of
74 ** A new class "gdb.FinishBreakpoint" is provided to catch the return
75 of a function. This class is based on the "finish" command
78 ** Type objects for struct and union types now allow access to
79 the fields using standard Python dictionary (mapping) methods.
80 For example, "some_type['myfield']" now works, as does
83 ** A new event "gdb.new_objfile" has been added, triggered by loading a
86 ** A new function, "deep_items" has been added to the gdb.types
87 module in the GDB Python modules library. This function returns
88 an iterator over the fields of a struct or union type. Unlike
89 the standard Python "iteritems" method, it will recursively traverse
94 ** "*stopped" events can report several new "reason"s, such as
97 ** Breakpoint changes are now notified using new async records, like
98 "=breakpoint-modified".
100 ** New command -ada-task-info.
102 * libthread-db-search-path now supports two special values: $sdir and $pdir.
103 $sdir specifies the default system locations of shared libraries.
104 $pdir specifies the directory where the libpthread used by the application
107 GDB no longer looks in $sdir and $pdir after it has searched the directories
108 mentioned in libthread-db-search-path. If you want to search those
109 directories, they must be specified in libthread-db-search-path.
110 The default value of libthread-db-search-path on GNU/Linux and Solaris
111 systems is now "$sdir:$pdir".
113 $pdir is not supported by gdbserver, it is currently ignored.
114 $sdir is supported by gdbserver.
116 * New configure option --with-iconv-bin.
117 When using the internationalization support like the one in the GNU C
118 library, GDB will invoke the "iconv" program to get a list of supported
119 character sets. If this program lives in a non-standard location, one can
120 use this option to specify where to find it.
122 * When natively debugging programs on PowerPC BookE processors running
123 a Linux kernel version 2.6.34 or later, GDB supports masked hardware
124 watchpoints, which specify a mask in addition to an address to watch.
125 The mask specifies that some bits of an address (the bits which are
126 reset in the mask) should be ignored when matching the address accessed
127 by the inferior against the watchpoint address. See the "PowerPC Embedded"
128 section in the user manual for more details.
130 * The new option --once causes GDBserver to stop listening for connections once
131 the first connection is made. The listening port used by GDBserver will
132 become available after that.
134 * New commands "info macros" and "alias" have been added.
136 * New function parameters suffix @entry specifies value of function parameter
137 at the time the function got called. Entry values are available only since
143 "!" is now an alias of the "shell" command.
144 Note that no space is needed between "!" and SHELL COMMAND.
148 watch EXPRESSION mask MASK_VALUE
149 The watch command now supports the mask argument which allows creation
150 of masked watchpoints, if the current architecture supports this feature.
152 info auto-load-scripts [REGEXP]
153 This command was formerly named "maintenance print section-scripts".
154 It is now generally useful and is no longer a maintenance-only command.
156 info macro [-all] [--] MACRO
157 The info macro command has new options `-all' and `--'. The first for
158 printing all definitions of a macro. The second for explicitly specifying
159 the end of arguments and the beginning of the macro name in case the macro
160 name starts with a hyphen.
162 collect[/s] EXPRESSIONS
163 The tracepoint collect command now takes an optional modifier "/s"
164 that directs it to dereference pointer-to-character types and
165 collect the bytes of memory up to a zero byte. The behavior is
166 similar to what you see when you use the regular print command on a
167 string. An optional integer following the "/s" sets a bound on the
168 number of bytes that will be collected.
171 The trace start command now interprets any supplied arguments as a
172 note to be recorded with the trace run, with an effect similar to
173 setting the variable trace-notes.
176 The trace stop command now interprets any arguments as a note to be
177 mentioned along with the tstatus report that the trace was stopped
178 with a command. The effect is similar to setting the variable
181 * Tracepoints can now be enabled and disabled at any time after a trace
182 experiment has been started using the standard "enable" and "disable"
183 commands. It is now possible to start a trace experiment with no enabled
184 tracepoints; GDB will display a warning, but will allow the experiment to
185 begin, assuming that tracepoints will be enabled as needed while the trace
188 * Fast tracepoints on 32-bit x86-architectures can now be placed at
189 locations with 4-byte instructions, when they were previously
190 limited to locations with instructions of 5 bytes or longer.
196 Set the GDB prompt, and allow escape sequences to be inserted to
197 display miscellaneous information (see 'help set extended-prompt'
198 for the list of sequences). This prompt (and any information
199 accessed through the escape sequences) is updated every time the
202 set print entry-values (both|compact|default|if-needed|no|only|preferred)
203 show print entry-values
204 Set printing of frame argument values at function entry. In some cases
205 GDB can determine the value of function argument which was passed by the
206 function caller, even if the value was modified inside the called function.
208 set debug entry-values
209 show debug entry-values
210 Control display of debugging info for determining frame argument values at
211 function entry and virtual tail call frames.
213 set basenames-may-differ
214 show basenames-may-differ
215 Set whether a source file may have multiple base names.
216 (A "base name" is the name of a file with the directory part removed.
217 Example: The base name of "/home/user/hello.c" is "hello.c".)
218 If set, GDB will canonicalize file names (e.g., expand symlinks)
219 before comparing them. Canonicalization is an expensive operation,
220 but it allows the same file be known by more than one base name.
221 If not set (the default), all source files are assumed to have just
222 one base name, and gdb will do file name comparisons more efficiently.
228 Set a user name and notes for the current and any future trace runs.
229 This is useful for long-running and/or disconnected traces, to
230 inform others (or yourself) as to who is running the trace, supply
231 contact information, or otherwise explain what is going on.
234 show trace-stop-notes
235 Set a note attached to the trace run, that is displayed when the
236 trace has been stopped by a tstop command. This is useful for
237 instance as an explanation, if you are stopping a trace run that was
238 started by someone else.
244 Dynamically enable a tracepoint in a started trace experiment.
248 Dynamically disable a tracepoint in a started trace experiment.
252 Set the user and notes of the trace run.
256 Query the current status of a tracepoint.
260 Query the minimum length of instruction at which a fast tracepoint may
263 * Dcache size (number of lines) and line-size are now runtime-configurable
264 via "set dcache line" and "set dcache line-size" commands.
268 Texas Instruments TMS320C6x tic6x-*-*
272 Renesas RL78 rl78-*-elf
274 *** Changes in GDB 7.3.1
276 * The build failure for NetBSD and OpenBSD targets have now been fixed.
278 *** Changes in GDB 7.3
280 * GDB has a new command: "thread find [REGEXP]".
281 It finds the thread id whose name, target id, or thread extra info
282 matches the given regular expression.
284 * The "catch syscall" command now works on mips*-linux* targets.
286 * The -data-disassemble MI command now supports modes 2 and 3 for
287 dumping the instruction opcodes.
289 * New command line options
291 -data-directory DIR Specify DIR as the "data-directory".
292 This is mostly for testing purposes.
294 * The "maint set python auto-load on|off" command has been renamed to
295 "set auto-load-scripts on|off".
297 * GDB has a new command: "set directories".
298 It is like the "dir" command except that it replaces the
299 source path list instead of augmenting it.
301 * GDB now understands thread names.
303 On GNU/Linux, "info threads" will display the thread name as set by
304 prctl or pthread_setname_np.
306 There is also a new command, "thread name", which can be used to
307 assign a name internally for GDB to display.
310 Initial support for the OpenCL C language (http://www.khronos.org/opencl)
311 has been integrated into GDB.
315 ** The function gdb.Write now accepts an optional keyword 'stream'.
316 This keyword, when provided, will direct the output to either
317 stdout, stderr, or GDB's logging output.
319 ** Parameters can now be be sub-classed in Python, and in particular
320 you may implement the get_set_doc and get_show_doc functions.
321 This improves how Parameter set/show documentation is processed
322 and allows for more dynamic content.
324 ** Symbols, Symbol Table, Symbol Table and Line, Object Files,
325 Inferior, Inferior Thread, Blocks, and Block Iterator APIs now
326 have an is_valid method.
328 ** Breakpoints can now be sub-classed in Python, and in particular
329 you may implement a 'stop' function that is executed each time
330 the inferior reaches that breakpoint.
332 ** New function gdb.lookup_global_symbol looks up a global symbol.
334 ** GDB values in Python are now callable if the value represents a
335 function. For example, if 'some_value' represents a function that
336 takes two integer parameters and returns a value, you can call
337 that function like so:
339 result = some_value (10,20)
341 ** Module gdb.types has been added.
342 It contains a collection of utilities for working with gdb.Types objects:
343 get_basic_type, has_field, make_enum_dict.
345 ** Module gdb.printing has been added.
346 It contains utilities for writing and registering pretty-printers.
347 New classes: PrettyPrinter, SubPrettyPrinter,
348 RegexpCollectionPrettyPrinter.
349 New function: register_pretty_printer.
351 ** New commands "info pretty-printers", "enable pretty-printer" and
352 "disable pretty-printer" have been added.
354 ** gdb.parameter("directories") is now available.
356 ** New function gdb.newest_frame returns the newest frame in the
359 ** The gdb.InferiorThread class has a new "name" attribute. This
360 holds the thread's name.
362 ** Python Support for Inferior events.
363 Python scripts can add observers to be notified of events
364 occurring in the process being debugged.
365 The following events are currently supported:
366 - gdb.events.cont Continue event.
367 - gdb.events.exited Inferior exited event.
368 - gdb.events.stop Signal received, and Breakpoint hit events.
372 ** GDB now puts template parameters in scope when debugging in an
373 instantiation. For example, if you have:
375 template<int X> int func (void) { return X; }
377 then if you step into func<5>, "print X" will show "5". This
378 feature requires proper debuginfo support from the compiler; it
379 was added to GCC 4.5.
381 ** The motion commands "next", "finish", "until", and "advance" now
382 work better when exceptions are thrown. In particular, GDB will
383 no longer lose control of the inferior; instead, the GDB will
384 stop the inferior at the point at which the exception is caught.
385 This functionality requires a change in the exception handling
386 code that was introduced in GCC 4.5.
388 * GDB now follows GCC's rules on accessing volatile objects when
389 reading or writing target state during expression evaluation.
390 One notable difference to prior behavior is that "print x = 0"
391 no longer generates a read of x; the value of the assignment is
392 now always taken directly from the value being assigned.
394 * GDB now has some support for using labels in the program's source in
395 linespecs. For instance, you can use "advance label" to continue
396 execution to a label.
398 * GDB now has support for reading and writing a new .gdb_index
399 section. This section holds a fast index of DWARF debugging
400 information and can be used to greatly speed up GDB startup and
401 operation. See the documentation for `save gdb-index' for details.
403 * The "watch" command now accepts an optional "-location" argument.
404 When used, this causes GDB to watch the memory referred to by the
405 expression. Such a watchpoint is never deleted due to it going out
408 * GDB now supports thread debugging of core dumps on GNU/Linux.
410 GDB now activates thread debugging using the libthread_db library
411 when debugging GNU/Linux core dumps, similarly to when debugging
412 live processes. As a result, when debugging a core dump file, GDB
413 is now able to display pthread_t ids of threads. For example, "info
414 threads" shows the same output as when debugging the process when it
415 was live. In earlier releases, you'd see something like this:
418 * 1 LWP 6780 main () at main.c:10
420 While now you see this:
423 * 1 Thread 0x7f0f5712a700 (LWP 6780) main () at main.c:10
425 It is also now possible to inspect TLS variables when debugging core
428 When debugging a core dump generated on a machine other than the one
429 used to run GDB, you may need to point GDB at the correct
430 libthread_db library with the "set libthread-db-search-path"
431 command. See the user manual for more details on this command.
433 * When natively debugging programs on PowerPC BookE processors running
434 a Linux kernel version 2.6.34 or later, GDB supports ranged breakpoints,
435 which stop execution of the inferior whenever it executes an instruction
436 at any address within the specified range. See the "PowerPC Embedded"
437 section in the user manual for more details.
439 * New features in the GDB remote stub, GDBserver
441 ** GDBserver is now supported on PowerPC LynxOS (versions 4.x and 5.x),
442 and i686 LynxOS (version 5.x).
444 ** GDBserver is now supported on Blackfin Linux.
446 * New native configurations
448 ia64 HP-UX ia64-*-hpux*
452 Analog Devices, Inc. Blackfin Processor bfin-*
454 * Ada task switching is now supported on sparc-elf targets when
455 debugging a program using the Ravenscar Profile. For more information,
456 see the "Tasking Support when using the Ravenscar Profile" section
457 in the GDB user manual.
459 * Guile support was removed.
461 * New features in the GNU simulator
463 ** The --map-info flag lists all known core mappings.
465 ** CFI flashes may be simulated via the "cfi" device.
467 *** Changes in GDB 7.2
469 * Shared library support for remote targets by default
471 When GDB is configured for a generic, non-OS specific target, like
472 for example, --target=arm-eabi or one of the many *-*-elf targets,
473 GDB now queries remote stubs for loaded shared libraries using the
474 `qXfer:libraries:read' packet. Previously, shared library support
475 was always disabled for such configurations.
479 ** Argument Dependent Lookup (ADL)
481 In C++ ADL lookup directs function search to the namespaces of its
482 arguments even if the namespace has not been imported.
492 Here the compiler will search for `foo' in the namespace of 'b'
493 and find A::foo. GDB now supports this. This construct is commonly
494 used in the Standard Template Library for operators.
496 ** Improved User Defined Operator Support
498 In addition to member operators, GDB now supports lookup of operators
499 defined in a namespace and imported with a `using' directive, operators
500 defined in the global scope, operators imported implicitly from an
501 anonymous namespace, and the ADL operators mentioned in the previous
503 GDB now also supports proper overload resolution for all the previously
504 mentioned flavors of operators.
506 ** static const class members
508 Printing of static const class members that are initialized in the
509 class definition has been fixed.
511 * Windows Thread Information Block access.
513 On Windows targets, GDB now supports displaying the Windows Thread
514 Information Block (TIB) structure. This structure is visible either
515 by using the new command `info w32 thread-information-block' or, by
516 dereferencing the new convenience variable named `$_tlb', a
517 thread-specific pointer to the TIB. This feature is also supported
518 when remote debugging using GDBserver.
522 Static tracepoints are calls in the user program into a tracing
523 library. One such library is a port of the LTTng kernel tracer to
524 userspace --- UST (LTTng Userspace Tracer, http://lttng.org/ust).
525 When debugging with GDBserver, GDB now supports combining the GDB
526 tracepoint machinery with such libraries. For example: the user can
527 use GDB to probe a static tracepoint marker (a call from the user
528 program into the tracing library) with the new "strace" command (see
529 "New commands" below). This creates a "static tracepoint" in the
530 breakpoint list, that can be manipulated with the same feature set
531 as fast and regular tracepoints. E.g., collect registers, local and
532 global variables, collect trace state variables, and define
533 tracepoint conditions. In addition, the user can collect extra
534 static tracepoint marker specific data, by collecting the new
535 $_sdata internal variable. When analyzing the trace buffer, you can
536 inspect $_sdata like any other variable available to GDB. For more
537 information, see the "Tracepoints" chapter in GDB user manual. New
538 remote packets have been defined to support static tracepoints, see
539 the "New remote packets" section below.
541 * Better reconstruction of tracepoints after disconnected tracing
543 GDB will attempt to download the original source form of tracepoint
544 definitions when starting a trace run, and then will upload these
545 upon reconnection to the target, resulting in a more accurate
546 reconstruction of the tracepoints that are in use on the target.
550 You can now exercise direct control over the ways that GDB can
551 affect your program. For instance, you can disallow the setting of
552 breakpoints, so that the program can run continuously (assuming
553 non-stop mode). In addition, the "observer" variable is available
554 to switch all of the different controls; in observer mode, GDB
555 cannot affect the target's behavior at all, which is useful for
556 tasks like diagnosing live systems in the field.
558 * The new convenience variable $_thread holds the number of the
565 Return the address of the Windows Thread Information Block of a given thread.
569 In response to several of the tracepoint packets, the target may now
570 also respond with a number of intermediate `qRelocInsn' request
571 packets before the final result packet, to have GDB handle
572 relocating an instruction to execute at a different address. This
573 is particularly useful for stubs that support fast tracepoints. GDB
574 reports support for this feature in the qSupported packet.
578 List static tracepoint markers in the target program.
582 List static tracepoint markers at a given address in the target
585 qXfer:statictrace:read
587 Read the static trace data collected (by a `collect $_sdata'
588 tracepoint action). The remote stub reports support for this packet
589 to gdb's qSupported query.
593 Send the current settings of GDB's permission flags.
597 Send part of the source (textual) form of a tracepoint definition,
598 which includes location, conditional, and action list.
600 * The source command now accepts a -s option to force searching for the
601 script in the source search path even if the script name specifies
604 * New features in the GDB remote stub, GDBserver
606 - GDBserver now support tracepoints (including fast tracepoints, and
607 static tracepoints). The feature is currently supported by the
608 i386-linux and amd64-linux builds. See the "Tracepoints support
609 in gdbserver" section in the manual for more information.
611 GDBserver JIT compiles the tracepoint's conditional agent
612 expression bytecode into native code whenever possible for low
613 overhead dynamic tracepoints conditionals. For such tracepoints,
614 an expression that examines program state is evaluated when the
615 tracepoint is reached, in order to determine whether to capture
616 trace data. If the condition is simple and false, processing the
617 tracepoint finishes very quickly and no data is gathered.
619 GDBserver interfaces with the UST (LTTng Userspace Tracer) library
620 for static tracepoints support.
622 - GDBserver now supports x86_64 Windows 64-bit debugging.
624 * GDB now sends xmlRegisters= in qSupported packet to indicate that
625 it understands register description.
627 * The --batch flag now disables pagination and queries.
629 * X86 general purpose registers
631 GDB now supports reading/writing byte, word and double-word x86
632 general purpose registers directly. This means you can use, say,
633 $ah or $ax to refer, respectively, to the byte register AH and
634 16-bit word register AX that are actually portions of the 32-bit
635 register EAX or 64-bit register RAX.
637 * The `commands' command now accepts a range of breakpoints to modify.
638 A plain `commands' following a command that creates multiple
639 breakpoints affects all the breakpoints set by that command. This
640 applies to breakpoints set by `rbreak', and also applies when a
641 single `break' command creates multiple breakpoints (e.g.,
642 breakpoints on overloaded c++ functions).
644 * The `rbreak' command now accepts a filename specification as part of
645 its argument, limiting the functions selected by the regex to those
646 in the specified file.
648 * Support for remote debugging Windows and SymbianOS shared libraries
649 from Unix hosts has been improved. Non Windows GDB builds now can
650 understand target reported file names that follow MS-DOS based file
651 system semantics, such as file names that include drive letters and
652 use the backslash character as directory separator. This makes it
653 possible to transparently use the "set sysroot" and "set
654 solib-search-path" on Unix hosts to point as host copies of the
655 target's shared libraries. See the new command "set
656 target-file-system-kind" described below, and the "Commands to
657 specify files" section in the user manual for more information.
661 eval template, expressions...
662 Convert the values of one or more expressions under the control
663 of the string template to a command line, and call it.
665 set target-file-system-kind unix|dos-based|auto
666 show target-file-system-kind
667 Set or show the assumed file system kind for target reported file
670 save breakpoints <filename>
671 Save all current breakpoint definitions to a file suitable for use
672 in a later debugging session. To read the saved breakpoint
673 definitions, use the `source' command.
675 `save tracepoints' is a new alias for `save-tracepoints'. The latter
678 info static-tracepoint-markers
679 Display information about static tracepoint markers in the target.
681 strace FN | FILE:LINE | *ADDR | -m MARKER_ID
682 Define a static tracepoint by probing a marker at the given
683 function, line, address, or marker ID.
687 Enable and disable observer mode.
689 set may-write-registers on|off
690 set may-write-memory on|off
691 set may-insert-breakpoints on|off
692 set may-insert-tracepoints on|off
693 set may-insert-fast-tracepoints on|off
694 set may-interrupt on|off
695 Set individual permissions for GDB effects on the target. Note that
696 some of these settings can have undesirable or surprising
697 consequences, particularly when changed in the middle of a session.
698 For instance, disabling the writing of memory can prevent
699 breakpoints from being inserted, cause single-stepping to fail, or
700 even crash your program, if you disable after breakpoints have been
701 inserted. However, GDB should not crash.
703 set record memory-query on|off
704 show record memory-query
705 Control whether to stop the inferior if memory changes caused
706 by an instruction cannot be recorded.
711 The disassemble command now supports "start,+length" form of two arguments.
715 ** GDB now provides a new directory location, called the python directory,
716 where Python scripts written for GDB can be installed. The location
717 of that directory is <data-directory>/python, where <data-directory>
718 is the GDB data directory. For more details, see section `Scripting
719 GDB using Python' in the manual.
721 ** The GDB Python API now has access to breakpoints, symbols, symbol
722 tables, program spaces, inferiors, threads and frame's code blocks.
723 Additionally, GDB Parameters can now be created from the API, and
724 manipulated via set/show in the CLI.
726 ** New functions gdb.target_charset, gdb.target_wide_charset,
727 gdb.progspaces, gdb.current_progspace, and gdb.string_to_argv.
729 ** New exception gdb.GdbError.
731 ** Pretty-printers are now also looked up in the current program space.
733 ** Pretty-printers can now be individually enabled and disabled.
735 ** GDB now looks for names of Python scripts to auto-load in a
736 special section named `.debug_gdb_scripts', in addition to looking
737 for a OBJFILE-gdb.py script when OBJFILE is read by the debugger.
739 * Tracepoint actions were unified with breakpoint commands. In particular,
740 there are no longer differences in "info break" output for breakpoints and
741 tracepoints and the "commands" command can be used for both tracepoints and
746 ARM Symbian arm*-*-symbianelf*
748 * D language support.
749 GDB now supports debugging programs written in the D programming
752 * GDB now supports the extended ptrace interface for PowerPC which is
753 available since Linux kernel version 2.6.34. This automatically enables
754 any hardware breakpoints and additional hardware watchpoints available in
755 the processor. The old ptrace interface exposes just one hardware
756 watchpoint and no hardware breakpoints.
758 * GDB is now able to use the Data Value Compare (DVC) register available on
759 embedded PowerPC processors to implement in hardware simple watchpoint
760 conditions of the form:
762 watch ADDRESS|VARIABLE if ADDRESS|VARIABLE == CONSTANT EXPRESSION
764 This works in native GDB running on Linux kernels with the extended ptrace
765 interface mentioned above.
767 *** Changes in GDB 7.1
773 GDB now supports importing of namespaces in C++. This enables the
774 user to inspect variables from imported namespaces. Support for
775 namepace aliasing has also been added. So, if a namespace is
776 aliased in the current scope (e.g. namepace C=A; ) the user can
777 print variables using the alias (e.g. (gdb) print C::x).
781 All known bugs relating to the printing of virtual base class were
782 fixed. It is now possible to call overloaded static methods using a
787 The C++ cast operators static_cast<>, dynamic_cast<>, const_cast<>,
788 and reinterpret_cast<> are now handled by the C++ expression parser.
792 Xilinx MicroBlaze microblaze-*-*
797 Xilinx MicroBlaze microblaze
800 * Multi-program debugging.
802 GDB now has support for multi-program (a.k.a. multi-executable or
803 multi-exec) debugging. This allows for debugging multiple inferiors
804 simultaneously each running a different program under the same GDB
805 session. See "Debugging Multiple Inferiors and Programs" in the
806 manual for more information. This implied some user visible changes
807 in the multi-inferior support. For example, "info inferiors" now
808 lists inferiors that are not running yet or that have exited
809 already. See also "New commands" and "New options" below.
811 * New tracing features
813 GDB's tracepoint facility now includes several new features:
815 ** Trace state variables
817 GDB tracepoints now include support for trace state variables, which
818 are variables managed by the target agent during a tracing
819 experiment. They are useful for tracepoints that trigger each
820 other, so for instance one tracepoint can count hits in a variable,
821 and then a second tracepoint has a condition that is true when the
822 count reaches a particular value. Trace state variables share the
823 $-syntax of GDB convenience variables, and can appear in both
824 tracepoint actions and condition expressions. Use the "tvariable"
825 command to create, and "info tvariables" to view; see "Trace State
826 Variables" in the manual for more detail.
830 GDB now includes an option for defining fast tracepoints, which
831 targets may implement more efficiently, such as by installing a jump
832 into the target agent rather than a trap instruction. The resulting
833 speedup can be by two orders of magnitude or more, although the
834 tradeoff is that some program locations on some target architectures
835 might not allow fast tracepoint installation, for instance if the
836 instruction to be replaced is shorter than the jump. To request a
837 fast tracepoint, use the "ftrace" command, with syntax identical to
838 the regular trace command.
840 ** Disconnected tracing
842 It is now possible to detach GDB from the target while it is running
843 a trace experiment, then reconnect later to see how the experiment
844 is going. In addition, a new variable disconnected-tracing lets you
845 tell the target agent whether to continue running a trace if the
846 connection is lost unexpectedly.
850 GDB now has the ability to save the trace buffer into a file, and
851 then use that file as a target, similarly to you can do with
852 corefiles. You can select trace frames, print data that was
853 collected in them, and use tstatus to display the state of the
854 tracing run at the moment that it was saved. To create a trace
855 file, use "tsave <filename>", and to use it, do "target tfile
858 ** Circular trace buffer
860 You can ask the target agent to handle the trace buffer as a
861 circular buffer, discarding the oldest trace frames to make room for
862 newer ones, by setting circular-trace-buffer to on. This feature may
863 not be available for all target agents.
868 The disassemble command, when invoked with two arguments, now requires
869 the arguments to be comma-separated.
872 The info variables command now displays variable definitions. Files
873 which only declare a variable are not shown.
876 The source command is now capable of sourcing Python scripts.
877 This feature is dependent on the debugger being build with Python
880 Related to this enhancement is also the introduction of a new command
881 "set script-extension" (see below).
883 * New commands (for set/show, see "New options" below)
885 record save [<FILENAME>]
886 Save a file (in core file format) containing the process record
887 execution log for replay debugging at a later time.
889 record restore <FILENAME>
890 Restore the process record execution log that was saved at an
891 earlier time, for replay debugging.
893 add-inferior [-copies <N>] [-exec <FILENAME>]
896 clone-inferior [-copies <N>] [ID]
897 Make a new inferior ready to execute the same program another
903 maint info program-spaces
904 List the program spaces loaded into GDB.
906 set remote interrupt-sequence [Ctrl-C | BREAK | BREAK-g]
907 show remote interrupt-sequence
908 Allow the user to select one of ^C, a BREAK signal or BREAK-g
909 as the sequence to the remote target in order to interrupt the execution.
910 Ctrl-C is a default. Some system prefers BREAK which is high level of
911 serial line for some certain time. Linux kernel prefers BREAK-g, a.k.a
912 Magic SysRq g. It is BREAK signal and character 'g'.
914 set remote interrupt-on-connect [on | off]
915 show remote interrupt-on-connect
916 When interrupt-on-connect is ON, gdb sends interrupt-sequence to
917 remote target when gdb connects to it. This is needed when you debug
920 set remotebreak [on | off]
922 Deprecated. Use "set/show remote interrupt-sequence" instead.
924 tvariable $NAME [ = EXP ]
925 Create or modify a trace state variable.
928 List trace state variables and their values.
930 delete tvariable $NAME ...
931 Delete one or more trace state variables.
934 Evaluate the given expressions without collecting anything into the
935 trace buffer. (Valid in tracepoint actions only.)
937 ftrace FN / FILE:LINE / *ADDR
938 Define a fast tracepoint at the given function, line, or address.
940 * New expression syntax
942 GDB now parses the 0b prefix of binary numbers the same way as GCC does.
943 GDB now parses 0b101010 identically with 42.
947 set follow-exec-mode new|same
948 show follow-exec-mode
949 Control whether GDB reuses the same inferior across an exec call or
950 creates a new one. This is useful to be able to restart the old
951 executable after the inferior having done an exec call.
953 set default-collect EXPR, ...
955 Define a list of expressions to be collected at each tracepoint.
956 This is a useful way to ensure essential items are not overlooked,
957 such as registers or a critical global variable.
959 set disconnected-tracing
960 show disconnected-tracing
961 If set to 1, the target is instructed to continue tracing if it
962 loses its connection to GDB. If 0, the target is to stop tracing
965 set circular-trace-buffer
966 show circular-trace-buffer
967 If set to on, the target is instructed to use a circular trace buffer
968 and discard the oldest trace frames instead of stopping the trace due
969 to a full trace buffer. If set to off, the trace stops when the buffer
970 fills up. Some targets may not support this.
972 set script-extension off|soft|strict
973 show script-extension
974 If set to "off", the debugger does not perform any script language
975 recognition, and all sourced files are assumed to be GDB scripts.
976 If set to "soft" (the default), files are sourced according to
977 filename extension, falling back to GDB scripts if the first
979 If set to "strict", files are sourced according to filename extension.
981 set ada trust-PAD-over-XVS on|off
982 show ada trust-PAD-over-XVS
983 If off, activate a workaround against a bug in the debugging information
984 generated by the compiler for PAD types (see gcc/exp_dbug.ads in
985 the GCC sources for more information about the GNAT encoding and
986 PAD types in particular). It is always safe to set this option to
987 off, but this introduces a slight performance penalty. The default
990 * Python API Improvements
992 ** GDB provides the new class gdb.LazyString. This is useful in
993 some pretty-printing cases. The new method gdb.Value.lazy_string
994 provides a simple way to create objects of this type.
996 ** The fields returned by gdb.Type.fields now have an
997 `is_base_class' attribute.
999 ** The new method gdb.Type.range returns the range of an array type.
1001 ** The new method gdb.parse_and_eval can be used to parse and
1002 evaluate an expression.
1004 * New remote packets
1007 Define a trace state variable.
1010 Get the current value of a trace state variable.
1013 Set desired tracing behavior upon disconnection.
1016 Set the trace buffer to be linear or circular.
1019 Get data about the tracepoints currently in use.
1023 Process record now works correctly with hardware watchpoints.
1025 Multiple bug fixes have been made to the mips-irix port, making it
1026 much more reliable. In particular:
1027 - Debugging threaded applications is now possible again. Previously,
1028 GDB would hang while starting the program, or while waiting for
1029 the program to stop at a breakpoint.
1030 - Attaching to a running process no longer hangs.
1031 - An error occurring while loading a core file has been fixed.
1032 - Changing the value of the PC register now works again. This fixes
1033 problems observed when using the "jump" command, or when calling
1034 a function from GDB, or even when assigning a new value to $pc.
1035 - With the "finish" and "return" commands, the return value for functions
1036 returning a small array is now correctly printed.
1037 - It is now possible to break on shared library code which gets executed
1038 during a shared library init phase (code executed while executing
1039 their .init section). Previously, the breakpoint would have no effect.
1040 - GDB is now able to backtrace through the signal handler for
1041 non-threaded programs.
1043 PIE (Position Independent Executable) programs debugging is now supported.
1044 This includes debugging execution of PIC (Position Independent Code) shared
1045 libraries although for that, it should be possible to run such libraries as an
1048 *** Changes in GDB 7.0
1050 * GDB now has an interface for JIT compilation. Applications that
1051 dynamically generate code can create symbol files in memory and register
1052 them with GDB. For users, the feature should work transparently, and
1053 for JIT developers, the interface is documented in the GDB manual in the
1054 "JIT Compilation Interface" chapter.
1056 * Tracepoints may now be conditional. The syntax is as for
1057 breakpoints; either an "if" clause appended to the "trace" command,
1058 or the "condition" command is available. GDB sends the condition to
1059 the target for evaluation using the same bytecode format as is used
1060 for tracepoint actions.
1062 * The disassemble command now supports: an optional /r modifier, print the
1063 raw instructions in hex as well as in symbolic form, and an optional /m
1064 modifier to print mixed source+assembly.
1066 * Process record and replay
1068 In a architecture environment that supports ``process record and
1069 replay'', ``process record and replay'' target can record a log of
1070 the process execution, and replay it with both forward and reverse
1073 * Reverse debugging: GDB now has new commands reverse-continue, reverse-
1074 step, reverse-next, reverse-finish, reverse-stepi, reverse-nexti, and
1075 set execution-direction {forward|reverse}, for targets that support
1078 * GDB now supports hardware watchpoints on MIPS/Linux systems. This
1079 feature is available with a native GDB running on kernel version
1082 * GDB now has support for multi-byte and wide character sets on the
1083 target. Strings whose character type is wchar_t, char16_t, or
1084 char32_t are now correctly printed. GDB supports wide- and unicode-
1085 literals in C, that is, L'x', L"string", u'x', u"string", U'x', and
1086 U"string" syntax. And, GDB allows the "%ls" and "%lc" formats in
1087 `printf'. This feature requires iconv to work properly; if your
1088 system does not have a working iconv, GDB can use GNU libiconv. See
1089 the installation instructions for more information.
1091 * GDB now supports automatic retrieval of shared library files from
1092 remote targets. To use this feature, specify a system root that begins
1093 with the `remote:' prefix, either via the `set sysroot' command or via
1094 the `--with-sysroot' configure-time option.
1096 * "info sharedlibrary" now takes an optional regex of libraries to show,
1097 and it now reports if a shared library has no debugging information.
1099 * Commands `set debug-file-directory', `set solib-search-path' and `set args'
1100 now complete on file names.
1102 * When completing in expressions, gdb will attempt to limit
1103 completions to allowable structure or union fields, where appropriate.
1104 For instance, consider:
1106 # struct example { int f1; double f2; };
1107 # struct example variable;
1110 If the user types TAB at the end of this command line, the available
1111 completions will be "f1" and "f2".
1113 * Inlined functions are now supported. They show up in backtraces, and
1114 the "step", "next", and "finish" commands handle them automatically.
1116 * GDB now supports the token-splicing (##) and stringification (#)
1117 operators when expanding macros. It also supports variable-arity
1120 * GDB now supports inspecting extra signal information, exported by
1121 the new $_siginfo convenience variable. The feature is currently
1122 implemented on linux ARM, i386 and amd64.
1124 * GDB can now display the VFP floating point registers and NEON vector
1125 registers on ARM targets. Both ARM GNU/Linux native GDB and gdbserver
1126 can provide these registers (requires Linux 2.6.30 or later). Remote
1127 and simulator targets may also provide them.
1129 * New remote packets
1132 Search memory for a sequence of bytes.
1135 Turn off `+'/`-' protocol acknowledgments to permit more efficient
1136 operation over reliable transport links. Use of this packet is
1137 controlled by the `set remote noack-packet' command.
1140 Kill the process with the specified process ID. Use this in preference
1141 to `k' when multiprocess protocol extensions are supported.
1144 Obtains additional operating system information
1148 Read or write additional signal information.
1150 * Removed remote protocol undocumented extension
1152 An undocumented extension to the remote protocol's `S' stop reply
1153 packet that permited the stub to pass a process id was removed.
1154 Remote servers should use the `T' stop reply packet instead.
1156 * GDB now supports multiple function calling conventions according to the
1157 DWARF-2 DW_AT_calling_convention function attribute.
1159 * The SH target utilizes the aforementioned change to distinguish between gcc
1160 and Renesas calling convention. It also adds the new CLI commands
1161 `set/show sh calling-convention'.
1163 * GDB can now read compressed debug sections, as produced by GNU gold
1164 with the --compress-debug-sections=zlib flag.
1166 * 64-bit core files are now supported on AIX.
1168 * Thread switching is now supported on Tru64.
1170 * Watchpoints can now be set on unreadable memory locations, e.g. addresses
1171 which will be allocated using malloc later in program execution.
1173 * The qXfer:libraries:read remote procotol packet now allows passing a
1174 list of section offsets.
1176 * On GNU/Linux, GDB can now attach to stopped processes. Several race
1177 conditions handling signals delivered during attach or thread creation
1178 have also been fixed.
1180 * GDB now supports the use of DWARF boolean types for Ada's type Boolean.
1181 From the user's standpoint, all unqualified instances of True and False
1182 are treated as the standard definitions, regardless of context.
1184 * GDB now parses C++ symbol and type names more flexibly. For
1187 template<typename T> class C { };
1190 GDB will now correctly handle all of:
1192 ptype C<char const *>
1193 ptype C<char const*>
1194 ptype C<const char *>
1195 ptype C<const char*>
1197 * New features in the GDB remote stub, gdbserver
1199 - The "--wrapper" command-line argument tells gdbserver to use a
1200 wrapper program to launch programs for debugging.
1202 - On PowerPC and S/390 targets, it is now possible to use a single
1203 gdbserver executable to debug both 32-bit and 64-bit programs.
1204 (This requires gdbserver itself to be built as a 64-bit executable.)
1206 - gdbserver uses the new noack protocol mode for TCP connections to
1207 reduce communications latency, if also supported and enabled in GDB.
1209 - Support for the sparc64-linux-gnu target is now included in
1212 - The amd64-linux build of gdbserver now supports debugging both
1213 32-bit and 64-bit programs.
1215 - The i386-linux, amd64-linux, and i386-win32 builds of gdbserver
1216 now support hardware watchpoints, and will use them automatically
1221 GDB now has support for scripting using Python. Whether this is
1222 available is determined at configure time.
1224 New GDB commands can now be written in Python.
1226 * Ada tasking support
1228 Ada tasks can now be inspected in GDB. The following commands have
1232 Print the list of Ada tasks.
1234 Print detailed information about task number N.
1236 Print the task number of the current task.
1238 Switch the context of debugging to task number N.
1240 * Support for user-defined prefixed commands. The "define" command can
1241 add new commands to existing prefixes, e.g. "target".
1243 * Multi-inferior, multi-process debugging.
1245 GDB now has generalized support for multi-inferior debugging. See
1246 "Debugging Multiple Inferiors" in the manual for more information.
1247 Although availability still depends on target support, the command
1248 set is more uniform now. The GNU/Linux specific multi-forks support
1249 has been migrated to this new framework. This implied some user
1250 visible changes; see "New commands" and also "Removed commands"
1253 * Target descriptions can now describe the target OS ABI. See the
1254 "Target Description Format" section in the user manual for more
1257 * Target descriptions can now describe "compatible" architectures
1258 to indicate that the target can execute applications for a different
1259 architecture in addition to those for the main target architecture.
1260 See the "Target Description Format" section in the user manual for
1263 * Multi-architecture debugging.
1265 GDB now includes general supports for debugging applications on
1266 hybrid systems that use more than one single processor architecture
1267 at the same time. Each such hybrid architecture still requires
1268 specific support to be added. The only hybrid architecture supported
1269 in this version of GDB is the Cell Broadband Engine.
1271 * GDB now supports integrated debugging of Cell/B.E. applications that
1272 use both the PPU and SPU architectures. To enable support for hybrid
1273 Cell/B.E. debugging, you need to configure GDB to support both the
1274 powerpc-linux or powerpc64-linux and the spu-elf targets, using the
1275 --enable-targets configure option.
1277 * Non-stop mode debugging.
1279 For some targets, GDB now supports an optional mode of operation in
1280 which you can examine stopped threads while other threads continue
1281 to execute freely. This is referred to as non-stop mode, with the
1282 old mode referred to as all-stop mode. See the "Non-Stop Mode"
1283 section in the user manual for more information.
1285 To be able to support remote non-stop debugging, a remote stub needs
1286 to implement the non-stop mode remote protocol extensions, as
1287 described in the "Remote Non-Stop" section of the user manual. The
1288 GDB remote stub, gdbserver, has been adjusted to support these
1289 extensions on linux targets.
1291 * New commands (for set/show, see "New options" below)
1293 catch syscall [NAME(S) | NUMBER(S)]
1294 Catch system calls. Arguments, which should be names of system
1295 calls or their numbers, mean catch only those syscalls. Without
1296 arguments, every syscall will be caught. When the inferior issues
1297 any of the specified syscalls, GDB will stop and announce the system
1298 call, both when it is called and when its call returns. This
1299 feature is currently available with a native GDB running on the
1300 Linux Kernel, under the following architectures: x86, x86_64,
1301 PowerPC and PowerPC64.
1303 find [/size-char] [/max-count] start-address, end-address|+search-space-size,
1305 Search memory for a sequence of bytes.
1307 maint set python print-stack
1308 maint show python print-stack
1309 Show a stack trace when an error is encountered in a Python script.
1312 Invoke CODE by passing it to the Python interpreter.
1317 These allow macros to be defined, undefined, and listed
1321 Show operating system information about processes.
1324 List the inferiors currently under GDB's control.
1327 Switch focus to inferior number NUM.
1330 Detach from inferior number NUM.
1333 Kill inferior number NUM.
1337 set spu stop-on-load
1338 show spu stop-on-load
1339 Control whether to stop for new SPE threads during Cell/B.E. debugging.
1341 set spu auto-flush-cache
1342 show spu auto-flush-cache
1343 Control whether to automatically flush the software-managed cache
1344 during Cell/B.E. debugging.
1346 set sh calling-convention
1347 show sh calling-convention
1348 Control the calling convention used when calling SH target functions.
1351 show debug timestamp
1352 Control display of timestamps with GDB debugging output.
1354 set disassemble-next-line
1355 show disassemble-next-line
1356 Control display of disassembled source lines or instructions when
1359 set remote noack-packet
1360 show remote noack-packet
1361 Set/show the use of remote protocol QStartNoAckMode packet. See above
1362 under "New remote packets."
1364 set remote query-attached-packet
1365 show remote query-attached-packet
1366 Control use of remote protocol `qAttached' (query-attached) packet.
1368 set remote read-siginfo-object
1369 show remote read-siginfo-object
1370 Control use of remote protocol `qXfer:siginfo:read' (read-siginfo-object)
1373 set remote write-siginfo-object
1374 show remote write-siginfo-object
1375 Control use of remote protocol `qXfer:siginfo:write' (write-siginfo-object)
1378 set remote reverse-continue
1379 show remote reverse-continue
1380 Control use of remote protocol 'bc' (reverse-continue) packet.
1382 set remote reverse-step
1383 show remote reverse-step
1384 Control use of remote protocol 'bs' (reverse-step) packet.
1386 set displaced-stepping
1387 show displaced-stepping
1388 Control displaced stepping mode. Displaced stepping is a way to
1389 single-step over breakpoints without removing them from the debuggee.
1390 Also known as "out-of-line single-stepping".
1393 show debug displaced
1394 Control display of debugging info for displaced stepping.
1396 maint set internal-error
1397 maint show internal-error
1398 Control what GDB does when an internal error is detected.
1400 maint set internal-warning
1401 maint show internal-warning
1402 Control what GDB does when an internal warning is detected.
1407 Use a wrapper program to launch programs for debugging.
1409 set multiple-symbols (all|ask|cancel)
1410 show multiple-symbols
1411 The value of this variable can be changed to adjust the debugger behavior
1412 when an expression or a breakpoint location contains an ambiguous symbol
1413 name (an overloaded function name, for instance).
1415 set breakpoint always-inserted
1416 show breakpoint always-inserted
1417 Keep breakpoints always inserted in the target, as opposed to inserting
1418 them when resuming the target, and removing them when the target stops.
1419 This option can improve debugger performance on slow remote targets.
1421 set arm fallback-mode (arm|thumb|auto)
1422 show arm fallback-mode
1423 set arm force-mode (arm|thumb|auto)
1425 These commands control how ARM GDB determines whether instructions
1426 are ARM or Thumb. The default for both settings is auto, which uses
1427 the current CPSR value for instructions without symbols; previous
1428 versions of GDB behaved as if "set arm fallback-mode arm".
1430 set disable-randomization
1431 show disable-randomization
1432 Standalone programs run with the virtual address space randomization enabled
1433 by default on some platforms. This option keeps the addresses stable across
1434 multiple debugging sessions.
1438 Control whether other threads are stopped or not when some thread hits
1443 Requests that asynchronous execution is enabled in the target, if available.
1444 In this case, it's possible to resume target in the background, and interact
1445 with GDB while the target is running. "show target-async" displays the
1446 current state of asynchronous execution of the target.
1448 set target-wide-charset
1449 show target-wide-charset
1450 The target-wide-charset is the name of the character set that GDB
1451 uses when printing characters whose type is wchar_t.
1453 set tcp auto-retry (on|off)
1455 set tcp connect-timeout
1456 show tcp connect-timeout
1457 These commands allow GDB to retry failed TCP connections to a remote stub
1458 with a specified timeout period; this is useful if the stub is launched
1459 in parallel with GDB but may not be ready to accept connections immediately.
1461 set libthread-db-search-path
1462 show libthread-db-search-path
1463 Control list of directories which GDB will search for appropriate
1466 set schedule-multiple (on|off)
1467 show schedule-multiple
1468 Allow GDB to resume all threads of all processes or only threads of
1469 the current process.
1473 Use more aggressive caching for accesses to the stack. This improves
1474 performance of remote debugging (particularly backtraces) without
1475 affecting correctness.
1477 set interactive-mode (on|off|auto)
1478 show interactive-mode
1479 Control whether GDB runs in interactive mode (on) or not (off).
1480 When in interactive mode, GDB waits for the user to answer all
1481 queries. Otherwise, GDB does not wait and assumes the default
1482 answer. When set to auto (the default), GDB determines which
1483 mode to use based on the stdin settings.
1488 For program forks, this is replaced by the new more generic `info
1489 inferiors' command. To list checkpoints, you can still use the
1490 `info checkpoints' command, which was an alias for the `info forks'
1494 Replaced by the new `inferior' command. To switch between
1495 checkpoints, you can still use the `restart' command, which was an
1496 alias for the `fork' command.
1499 This is removed, since some targets don't have a notion of
1500 processes. To switch between processes, you can still use the
1501 `inferior' command using GDB's own inferior number.
1504 For program forks, this is replaced by the new more generic `kill
1505 inferior' command. To delete a checkpoint, you can still use the
1506 `delete checkpoint' command, which was an alias for the `delete
1510 For program forks, this is replaced by the new more generic `detach
1511 inferior' command. To detach a checkpoint, you can still use the
1512 `detach checkpoint' command, which was an alias for the `detach
1515 * New native configurations
1517 x86/x86_64 Darwin i[34567]86-*-darwin*
1519 x86_64 MinGW x86_64-*-mingw*
1523 Lattice Mico32 lm32-*
1524 x86 DICOS i[34567]86-*-dicos*
1525 x86_64 DICOS x86_64-*-dicos*
1528 * The GDB remote stub, gdbserver, now supports x86 Windows CE
1529 (mingw32ce) debugging.
1535 These commands were actually not implemented on any target.
1537 *** Changes in GDB 6.8
1539 * New native configurations
1541 NetBSD/hppa hppa*-*netbsd*
1542 Xtensa GNU/Linux xtensa*-*-linux*
1546 NetBSD/hppa hppa*-*-netbsd*
1547 Xtensa GNU/Lunux xtensa*-*-linux*
1549 * Change in command line behavior -- corefiles vs. process ids.
1551 When the '-p NUMBER' or '--pid NUMBER' options are used, and
1552 attaching to process NUMBER fails, GDB no longer attempts to open a
1553 core file named NUMBER. Attaching to a program using the -c option
1554 is no longer supported. Instead, use the '-p' or '--pid' options.
1556 * GDB can now be built as a native debugger for debugging Windows x86
1557 (mingw32) Portable Executable (PE) programs.
1559 * Pending breakpoints no longer change their number when their address
1562 * GDB now supports breakpoints with multiple locations,
1563 including breakpoints on C++ constructors, inside C++ templates,
1564 and in inlined functions.
1566 * GDB's ability to debug optimized code has been improved. GDB more
1567 accurately identifies function bodies and lexical blocks that occupy
1568 more than one contiguous range of addresses.
1570 * Target descriptions can now describe registers for PowerPC.
1572 * The GDB remote stub, gdbserver, now supports the AltiVec and SPE
1573 registers on PowerPC targets.
1575 * The GDB remote stub, gdbserver, now supports thread debugging on GNU/Linux
1576 targets even when the libthread_db library is not available.
1578 * The GDB remote stub, gdbserver, now supports the new file transfer
1579 commands (remote put, remote get, and remote delete).
1581 * The GDB remote stub, gdbserver, now supports run and attach in
1582 extended-remote mode.
1584 * hppa*64*-*-hpux11* target broken
1585 The debugger is unable to start a program and fails with the following
1586 error: "Error trying to get information about dynamic linker".
1587 The gdb-6.7 release is also affected.
1589 * GDB now supports the --enable-targets= configure option to allow
1590 building a single GDB executable that supports multiple remote
1591 target architectures.
1593 * GDB now supports debugging C and C++ programs which use the
1594 Decimal Floating Point extension. In addition, the PowerPC target
1595 now has a set of pseudo-registers to inspect decimal float values
1596 stored in two consecutive float registers.
1598 * The -break-insert MI command can optionally create pending
1601 * Improved support for debugging Ada
1602 Many improvements to the Ada language support have been made. These
1604 - Better support for Ada2005 interface types
1605 - Improved handling of arrays and slices in general
1606 - Better support for Taft-amendment types
1607 - The '{type} ADDRESS' expression is now allowed on the left hand-side
1609 - Improved command completion in Ada
1612 * GDB on GNU/Linux and HP/UX can now debug through "exec" of a new
1617 set print frame-arguments (all|scalars|none)
1618 show print frame-arguments
1619 The value of this variable can be changed to control which argument
1620 values should be printed by the debugger when displaying a frame.
1625 Transfer files to and from a remote target, and delete remote files.
1632 Transfer files to and from a remote target, and delete remote files.
1634 * New remote packets
1641 Open, close, read, write, and delete files on the remote system.
1644 Attach to an existing process on the remote system, in extended-remote
1648 Run a new process on the remote system, in extended-remote mode.
1650 *** Changes in GDB 6.7
1652 * Resolved 101 resource leaks, null pointer dereferences, etc. in gdb,
1653 bfd, libiberty and opcodes, as revealed by static analysis donated by
1654 Coverity, Inc. (http://scan.coverity.com).
1656 * When looking up multiply-defined global symbols, GDB will now prefer the
1657 symbol definition in the current shared library if it was built using the
1658 -Bsymbolic linker option.
1660 * When the Text User Interface (TUI) is not configured, GDB will now
1661 recognize the -tui command-line option and print a message that the TUI
1664 * The GDB remote stub, gdbserver, now has lower overhead for high
1665 frequency signals (e.g. SIGALRM) via the QPassSignals packet.
1667 * GDB for MIPS targets now autodetects whether a remote target provides
1668 32-bit or 64-bit register values.
1670 * Support for C++ member pointers has been improved.
1672 * GDB now understands XML target descriptions, which specify the
1673 target's overall architecture. GDB can read a description from
1674 a local file or over the remote serial protocol.
1676 * Vectors of single-byte data use a new integer type which is not
1677 automatically displayed as character or string data.
1679 * The /s format now works with the print command. It displays
1680 arrays of single-byte integers and pointers to single-byte integers
1683 * Target descriptions can now describe target-specific registers,
1684 for architectures which have implemented the support (currently
1685 only ARM, M68K, and MIPS).
1687 * GDB and the GDB remote stub, gdbserver, now support the XScale
1690 * The GDB remote stub, gdbserver, has been updated to support
1691 ARM Windows CE (mingw32ce) debugging, and GDB Windows CE support
1692 has been rewritten to use the standard GDB remote protocol.
1694 * GDB can now step into C++ functions which are called through thunks.
1696 * GDB for the Cell/B.E. SPU now supports overlay debugging.
1698 * The GDB remote protocol "qOffsets" packet can now honor ELF segment
1699 layout. It also supports a TextSeg= and DataSeg= response when only
1700 segment base addresses (rather than offsets) are available.
1702 * The /i format now outputs any trailing branch delay slot instructions
1703 immediately following the last instruction within the count specified.
1705 * The GDB remote protocol "T" stop reply packet now supports a
1706 "library" response. Combined with the new "qXfer:libraries:read"
1707 packet, this response allows GDB to debug shared libraries on targets
1708 where the operating system manages the list of loaded libraries (e.g.
1709 Windows and SymbianOS).
1711 * The GDB remote stub, gdbserver, now supports dynamic link libraries
1712 (DLLs) on Windows and Windows CE targets.
1714 * GDB now supports a faster verification that a .debug file matches its binary
1715 according to its build-id signature, if the signature is present.
1721 Enable or disable hardware flow control (RTS/CTS) on the serial port
1722 when debugging using remote targets.
1724 set mem inaccessible-by-default
1725 show mem inaccessible-by-default
1726 If the target supplies a memory map, for instance via the remote
1727 protocol's "qXfer:memory-map:read" packet, setting this variable
1728 prevents GDB from accessing memory outside the memory map. This
1729 is useful for targets with memory mapped registers or which react
1730 badly to accesses of unmapped address space.
1732 set breakpoint auto-hw
1733 show breakpoint auto-hw
1734 If the target supplies a memory map, for instance via the remote
1735 protocol's "qXfer:memory-map:read" packet, setting this variable
1736 lets GDB use hardware breakpoints automatically for memory regions
1737 where it can not use software breakpoints. This covers both the
1738 "break" command and internal breakpoints used for other commands
1739 including "next" and "finish".
1742 catch exception unhandled
1743 Stop the program execution when Ada exceptions are raised.
1746 Stop the program execution when an Ada assertion failed.
1750 Set an alternate system root for target files. This is a more
1751 general version of "set solib-absolute-prefix", which is now
1752 an alias to "set sysroot".
1755 Provide extended SPU facility status information. This set of
1756 commands is available only when debugging the Cell/B.E. SPU
1759 * New native configurations
1761 OpenBSD/sh sh*-*openbsd*
1764 unset tdesc filename
1766 Use the specified local file as an XML target description, and do
1767 not query the target for its built-in description.
1771 OpenBSD/sh sh*-*-openbsd*
1772 MIPS64 GNU/Linux (gdbserver) mips64-linux-gnu
1773 Toshiba Media Processor mep-elf
1775 * New remote packets
1778 Ignore the specified signals; pass them directly to the debugged program
1779 without stopping other threads or reporting them to GDB.
1781 qXfer:features:read:
1782 Read an XML target description from the target, which describes its
1787 Read or write contents of an spufs file on the target system. These
1788 packets are available only on the Cell/B.E. SPU architecture.
1790 qXfer:libraries:read:
1791 Report the loaded shared libraries. Combined with new "T" packet
1792 response, this packet allows GDB to debug shared libraries on
1793 targets where the operating system manages the list of loaded
1794 libraries (e.g. Windows and SymbianOS).
1798 Support for these obsolete configurations has been removed.
1806 i[34567]86-*-lynxos*
1807 i[34567]86-*-netware*
1808 i[34567]86-*-sco3.2v5*
1809 i[34567]86-*-sco3.2v4*
1811 i[34567]86-*-sysv4.2*
1814 i[34567]86-*-unixware2*
1815 i[34567]86-*-unixware*
1824 * Other removed features
1831 Various m68k-only ROM monitors.
1838 Various Renesas ROM monitors and debugging interfaces for SH and
1843 Support for a Macraigor serial interface to on-chip debugging.
1844 GDB does not directly support the newer parallel or USB
1849 A debug information format. The predecessor to DWARF 2 and
1850 DWARF 3, which are still supported.
1852 Support for the HP aCC compiler on HP-UX/PA-RISC
1854 SOM-encapsulated symbolic debugging information, automatic
1855 invocation of pxdb, and the aCC custom C++ ABI. This does not
1856 affect HP-UX for Itanium or GCC for HP-UX/PA-RISC. Code compiled
1857 with aCC can still be debugged on an assembly level.
1859 MIPS ".pdr" sections
1861 A MIPS-specific format used to describe stack frame layout
1862 in debugging information.
1866 GDB could work with an older version of Guile to debug
1867 the interpreter and Scheme programs running in it.
1869 set mips stack-arg-size
1870 set mips saved-gpreg-size
1872 Use "set mips abi" to control parameter passing for MIPS.
1874 *** Changes in GDB 6.6
1879 Cell Broadband Engine SPU spu-elf
1881 * GDB can now be configured as a cross-debugger targeting native Windows
1882 (mingw32) or Cygwin. It can communicate with a remote debugging stub
1883 running on a Windows system over TCP/IP to debug Windows programs.
1885 * The GDB remote stub, gdbserver, has been updated to support Windows and
1886 Cygwin debugging. Both single-threaded and multi-threaded programs are
1889 * The "set trust-readonly-sections" command works again. This command was
1890 broken in GDB 6.3, 6.4, and 6.5.
1892 * The "load" command now supports writing to flash memory, if the remote
1893 stub provides the required support.
1895 * Support for GNU/Linux Thread Local Storage (TLS, per-thread variables) no
1896 longer requires symbolic debug information (e.g. DWARF-2).
1901 unset substitute-path
1902 show substitute-path
1903 Manage a list of substitution rules that GDB uses to rewrite the name
1904 of the directories where the sources are located. This can be useful
1905 for instance when the sources were moved to a different location
1906 between compilation and debugging.
1910 Print each CLI command as it is executed. Each command is prefixed with
1911 a number of `+' symbols representing the nesting depth.
1912 The source command now has a `-v' option to enable the same feature.
1916 The ARM Demon monitor support (RDP protocol, "target rdp").
1918 Kernel Object Display, an embedded debugging feature which only worked with
1919 an obsolete version of Cisco IOS.
1921 The 'set download-write-size' and 'show download-write-size' commands.
1923 * New remote packets
1926 Tell a stub about GDB client features, and request remote target features.
1927 The first feature implemented is PacketSize, which allows the target to
1928 specify the size of packets it can handle - to minimize the number of
1929 packets required and improve performance when connected to a remote
1933 Fetch an OS auxilliary vector from the remote stub. This packet is a
1934 more efficient replacement for qPart:auxv:read.
1936 qXfer:memory-map:read:
1937 Fetch a memory map from the remote stub, including information about
1938 RAM, ROM, and flash memory devices.
1943 Erase and program a flash memory device.
1945 * Removed remote packets
1948 This packet has been replaced by qXfer:auxv:read. Only GDB 6.4 and 6.5
1949 used it, and only gdbserver implemented it.
1951 *** Changes in GDB 6.5
1955 Renesas M32C/M16C m32c-elf
1957 Morpho Technologies ms1 ms1-elf
1961 init-if-undefined Initialize a convenience variable, but
1962 only if it doesn't already have a value.
1964 The following commands are presently only implemented for native GNU/Linux:
1966 checkpoint Save a snapshot of the program state.
1968 restart <n> Return the program state to a
1969 previously saved state.
1971 info checkpoints List currently saved checkpoints.
1973 delete-checkpoint <n> Delete a previously saved checkpoint.
1975 set|show detach-on-fork Tell gdb whether to detach from a newly
1976 forked process, or to keep debugging it.
1978 info forks List forks of the user program that
1979 are available to be debugged.
1981 fork <n> Switch to debugging one of several
1982 forks of the user program that are
1983 available to be debugged.
1985 delete-fork <n> Delete a fork from the list of forks
1986 that are available to be debugged (and
1987 kill the forked process).
1989 detach-fork <n> Delete a fork from the list of forks
1990 that are available to be debugged (and
1991 allow the process to continue).
1995 Morpho Technologies ms2 ms1-elf
1997 * Improved Windows host support
1999 GDB now builds as a cross debugger hosted on i686-mingw32, including
2000 native console support, and remote communications using either
2001 network sockets or serial ports.
2003 * Improved Modula-2 language support
2005 GDB can now print most types in the Modula-2 syntax. This includes:
2006 basic types, set types, record types, enumerated types, range types,
2007 pointer types and ARRAY types. Procedure var parameters are correctly
2008 printed and hexadecimal addresses and character constants are also
2009 written in the Modula-2 syntax. Best results can be obtained by using
2010 GNU Modula-2 together with the -gdwarf-2 command line option.
2014 The ARM rdi-share module.
2016 The Netware NLM debug server.
2018 *** Changes in GDB 6.4
2020 * New native configurations
2022 OpenBSD/arm arm*-*-openbsd*
2023 OpenBSD/mips64 mips64-*-openbsd*
2027 Morpho Technologies ms1 ms1-elf
2029 * New command line options
2031 --batch-silent As for --batch, but totally silent.
2032 --return-child-result The debugger will exist with the same value
2033 the child (debugged) program exited with.
2034 --eval-command COMMAND, -ex COMMAND
2035 Execute a single GDB CLI command. This may be
2036 specified multiple times and in conjunction
2037 with the --command (-x) option.
2039 * Deprecated commands removed
2041 The following commands, that were deprecated in 2000, have been
2045 set|show arm disassembly-flavor set|show arm disassembler
2046 othernames set arm disassembler
2047 set|show remotedebug set|show debug remote
2048 set|show archdebug set|show debug arch
2049 set|show eventdebug set|show debug event
2052 * New BSD user-level threads support
2054 It is now possible to debug programs using the user-level threads
2055 library on OpenBSD and FreeBSD. Currently supported (target)
2058 FreeBSD/amd64 x86_64-*-freebsd*
2059 FreeBSD/i386 i386-*-freebsd*
2060 OpenBSD/i386 i386-*-openbsd*
2062 Note that the new kernel threads libraries introduced in FreeBSD 5.x
2063 are not yet supported.
2065 * New support for Matsushita MN10300 w/sim added
2066 (Work in progress). mn10300-elf.
2068 * REMOVED configurations and files
2070 VxWorks and the XDR protocol *-*-vxworks
2071 Motorola MCORE mcore-*-*
2072 National Semiconductor NS32000 ns32k-*-*
2074 * New "set print array-indexes" command
2076 After turning this setting "on", GDB prints the index of each element
2077 when displaying arrays. The default is "off" to preserve the previous
2080 * VAX floating point support
2082 GDB now supports the not-quite-ieee VAX F and D floating point formats.
2084 * User-defined command support
2086 In addition to using $arg0..$arg9 for argument passing, it is now possible
2087 to use $argc to determine now many arguments have been passed. See the
2088 section on user-defined commands in the user manual for more information.
2090 *** Changes in GDB 6.3:
2092 * New command line option
2094 GDB now accepts -l followed by a number to set the timeout for remote
2097 * GDB works with GCC -feliminate-dwarf2-dups
2099 GDB now supports a more compact representation of DWARF-2 debug
2100 information using DW_FORM_ref_addr references. These are produced
2101 by GCC with the option -feliminate-dwarf2-dups and also by some
2102 proprietary compilers. With GCC, you must use GCC 3.3.4 or later
2103 to use -feliminate-dwarf2-dups.
2105 * Internationalization
2107 When supported by the host system, GDB will be built with
2108 internationalization (libintl). The task of marking up the sources is
2109 continued, we're looking forward to our first translation.
2113 Initial support for debugging programs compiled with the GNAT
2114 implementation of the Ada programming language has been integrated
2115 into GDB. In this release, support is limited to expression evaluation.
2117 * New native configurations
2119 GNU/Linux/m32r m32r-*-linux-gnu
2123 GDB's remote protocol now includes support for the 'p' packet. This
2124 packet is used to fetch individual registers from a remote inferior.
2126 * END-OF-LIFE registers[] compatibility module
2128 GDB's internal register infrastructure has been completely rewritten.
2129 The new infrastructure making possible the implementation of key new
2130 features including 32x64 (e.g., 64-bit amd64 GDB debugging a 32-bit
2133 GDB 6.3 will be the last release to include the the registers[]
2134 compatibility module that allowed out-of-date configurations to
2135 continue to work. This change directly impacts the following
2145 powerpc bdm protocol
2147 Unless there is activity to revive these configurations, they will be
2148 made OBSOLETE in GDB 6.4, and REMOVED from GDB 6.5.
2150 * OBSOLETE configurations and files
2152 Configurations that have been declared obsolete in this release have
2153 been commented out. Unless there is activity to revive these
2154 configurations, the next release of GDB will have their sources
2155 permanently REMOVED.
2164 *** Changes in GDB 6.2.1:
2166 * MIPS `break main; run' gave an heuristic-fence-post warning
2168 When attempting to run even a simple program, a warning about
2169 heuristic-fence-post being hit would be reported. This problem has
2172 * MIPS IRIX 'long double' crashed GDB
2174 When examining a long double variable, GDB would get a segmentation
2175 fault. The crash has been fixed (but GDB 6.2 cannot correctly examine
2176 IRIX long double values).
2180 A bug in the VAX stack code was causing problems with the "next"
2181 command. This problem has been fixed.
2183 *** Changes in GDB 6.2:
2185 * Fix for ``many threads''
2187 On GNU/Linux systems that use the NPTL threads library, a program
2188 rapidly creating and deleting threads would confuse GDB leading to the
2191 ptrace: No such process.
2192 thread_db_get_info: cannot get thread info: generic error
2194 This problem has been fixed.
2196 * "-async" and "-noasync" options removed.
2198 Support for the broken "-noasync" option has been removed (it caused
2201 * New ``start'' command.
2203 This command runs the program until the begining of the main procedure.
2205 * New BSD Kernel Data Access Library (libkvm) interface
2207 Using ``target kvm'' it is now possible to debug kernel core dumps and
2208 live kernel memory images on various FreeBSD, NetBSD and OpenBSD
2209 platforms. Currently supported (native-only) configurations are:
2211 FreeBSD/amd64 x86_64-*-freebsd*
2212 FreeBSD/i386 i?86-*-freebsd*
2213 NetBSD/i386 i?86-*-netbsd*
2214 NetBSD/m68k m68*-*-netbsd*
2215 NetBSD/sparc sparc-*-netbsd*
2216 OpenBSD/amd64 x86_64-*-openbsd*
2217 OpenBSD/i386 i?86-*-openbsd*
2218 OpenBSD/m68k m68*-openbsd*
2219 OpenBSD/sparc sparc-*-openbsd*
2221 * Signal trampoline code overhauled
2223 Many generic problems with GDB's signal handling code have been fixed.
2224 These include: backtraces through non-contiguous stacks; recognition
2225 of sa_sigaction signal trampolines; backtrace from a NULL pointer
2226 call; backtrace through a signal trampoline; step into and out of
2227 signal handlers; and single-stepping in the signal trampoline.
2229 Please note that kernel bugs are a limiting factor here. These
2230 features have been shown to work on an s390 GNU/Linux system that
2231 include a 2.6.8-rc1 kernel. Ref PR breakpoints/1702.
2233 * Cygwin support for DWARF 2 added.
2235 * New native configurations
2237 GNU/Linux/hppa hppa*-*-linux*
2238 OpenBSD/hppa hppa*-*-openbsd*
2239 OpenBSD/m68k m68*-*-openbsd*
2240 OpenBSD/m88k m88*-*-openbsd*
2241 OpenBSD/powerpc powerpc-*-openbsd*
2242 NetBSD/vax vax-*-netbsd*
2243 OpenBSD/vax vax-*-openbsd*
2245 * END-OF-LIFE frame compatibility module
2247 GDB's internal frame infrastructure has been completely rewritten.
2248 The new infrastructure making it possible to support key new features
2249 including DWARF 2 Call Frame Information. To aid in the task of
2250 migrating old configurations to this new infrastructure, a
2251 compatibility module, that allowed old configurations to continue to
2252 work, was also included.
2254 GDB 6.2 will be the last release to include this frame compatibility
2255 module. This change directly impacts the following configurations:
2265 Unless there is activity to revive these configurations, they will be
2266 made OBSOLETE in GDB 6.3, and REMOVED from GDB 6.4.
2268 * REMOVED configurations and files
2270 Sun 3, running SunOS 3 m68*-*-sunos3*
2271 Sun 3, running SunOS 4 m68*-*-sunos4*
2272 Sun 2, running SunOS 3 m68000-*-sunos3*
2273 Sun 2, running SunOS 4 m68000-*-sunos4*
2274 Motorola 680x0 running LynxOS m68*-*-lynxos*
2275 AT&T 3b1/Unix pc m68*-att-*
2276 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
2277 decstation mips-dec-* mips-little-*
2278 riscos mips-*-riscos* mips-*-sysv*
2279 sonymips mips-sony-*
2280 sysv mips*-*-sysv4* (IRIX 5/6 not included)
2282 *** Changes in GDB 6.1.1:
2284 * TUI (Text-mode User Interface) built-in (also included in GDB 6.1)
2286 The TUI (Text-mode User Interface) is now built as part of a default
2287 GDB configuration. It is enabled by either selecting the TUI with the
2288 command line option "-i=tui" or by running the separate "gdbtui"
2289 program. For more information on the TUI, see the manual "Debugging
2292 * Pending breakpoint support (also included in GDB 6.1)
2294 Support has been added to allow you to specify breakpoints in shared
2295 libraries that have not yet been loaded. If a breakpoint location
2296 cannot be found, and the "breakpoint pending" option is set to auto,
2297 GDB queries you if you wish to make the breakpoint pending on a future
2298 shared-library load. If and when GDB resolves the breakpoint symbol,
2299 the pending breakpoint is removed as one or more regular breakpoints
2302 Pending breakpoints are very useful for GCJ Java debugging.
2304 * Fixed ISO-C build problems
2306 The files bfd/elf-bfd.h, gdb/dictionary.c and gdb/types.c contained
2307 non ISO-C code that stopped them being built using a more strict ISO-C
2308 compiler (e.g., IBM's C compiler).
2310 * Fixed build problem on IRIX 5
2312 Due to header problems with <sys/proc.h>, the file gdb/proc-api.c
2313 wasn't able to compile compile on an IRIX 5 system.
2315 * Added execute permission to gdb/gdbserver/configure
2317 The shell script gdb/testsuite/gdb.stabs/configure lacked execute
2318 permission. This bug would cause configure to fail on a number of
2319 systems (Solaris, IRIX). Ref: server/519.
2321 * Fixed build problem on hpux2.0w-hp-hpux11.00 using the HP ANSI C compiler
2323 Older HPUX ANSI C compilers did not accept variable array sizes. somsolib.c
2324 has been updated to use constant array sizes.
2326 * Fixed a panic in the DWARF Call Frame Info code on Solaris 2.7
2328 GCC 3.3.2, on Solaris 2.7, includes the DW_EH_PE_funcrel encoding in
2329 its generated DWARF Call Frame Info. This encoding was causing GDB to
2330 panic, that panic has been fixed. Ref: gdb/1628.
2332 * Fixed a problem when examining parameters in shared library code.
2334 When examining parameters in optimized shared library code generated
2335 by a mainline GCC, GDB would incorrectly report ``Variable "..." is
2336 not available''. GDB now correctly displays the variable's value.
2338 *** Changes in GDB 6.1:
2340 * Removed --with-mmalloc
2342 Support for the mmalloc memory manager has been removed, as it
2343 conflicted with the internal gdb byte cache.
2345 * Changes in AMD64 configurations
2347 The AMD64 target now includes the %cs and %ss registers. As a result
2348 the AMD64 remote protocol has changed; this affects the floating-point
2349 and SSE registers. If you rely on those registers for your debugging,
2350 you should upgrade gdbserver on the remote side.
2352 * Revised SPARC target
2354 The SPARC target has been completely revised, incorporating the
2355 FreeBSD/sparc64 support that was added for GDB 6.0. As a result
2356 support for LynxOS and SunOS 4 has been dropped. Calling functions
2357 from within GDB on operating systems with a non-executable stack
2358 (Solaris, OpenBSD) now works.
2362 GDB has a new C++ demangler which does a better job on the mangled
2363 names generated by current versions of g++. It also runs faster, so
2364 with this and other changes gdb should now start faster on large C++
2367 * DWARF 2 Location Expressions
2369 GDB support for location expressions has been extended to support function
2370 arguments and frame bases. Older versions of GDB could crash when they
2373 * C++ nested types and namespaces
2375 GDB's support for nested types and namespaces in C++ has been
2376 improved, especially if you use the DWARF 2 debugging format. (This
2377 is the default for recent versions of GCC on most platforms.)
2378 Specifically, if you have a class "Inner" defined within a class or
2379 namespace "Outer", then GDB realizes that the class's name is
2380 "Outer::Inner", not simply "Inner". This should greatly reduce the
2381 frequency of complaints about not finding RTTI symbols. In addition,
2382 if you are stopped at inside of a function defined within a namespace,
2383 GDB modifies its name lookup accordingly.
2385 * New native configurations
2387 NetBSD/amd64 x86_64-*-netbsd*
2388 OpenBSD/amd64 x86_64-*-openbsd*
2389 OpenBSD/alpha alpha*-*-openbsd*
2390 OpenBSD/sparc sparc-*-openbsd*
2391 OpenBSD/sparc64 sparc64-*-openbsd*
2393 * New debugging protocols
2395 M32R with SDI protocol m32r-*-elf*
2397 * "set prompt-escape-char" command deleted.
2399 The command "set prompt-escape-char" has been deleted. This command,
2400 and its very obscure effet on GDB's prompt, was never documented,
2401 tested, nor mentioned in the NEWS file.
2403 * OBSOLETE configurations and files
2405 Configurations that have been declared obsolete in this release have
2406 been commented out. Unless there is activity to revive these
2407 configurations, the next release of GDB will have their sources
2408 permanently REMOVED.
2410 Sun 3, running SunOS 3 m68*-*-sunos3*
2411 Sun 3, running SunOS 4 m68*-*-sunos4*
2412 Sun 2, running SunOS 3 m68000-*-sunos3*
2413 Sun 2, running SunOS 4 m68000-*-sunos4*
2414 Motorola 680x0 running LynxOS m68*-*-lynxos*
2415 AT&T 3b1/Unix pc m68*-att-*
2416 Bull DPX2 (68k, System V release 3) m68*-bull-sysv*
2417 decstation mips-dec-* mips-little-*
2418 riscos mips-*-riscos* mips-*-sysv*
2419 sonymips mips-sony-*
2420 sysv mips*-*-sysv4* (IRIX 5/6 not included)
2422 * REMOVED configurations and files
2424 SGI Irix-4.x mips-sgi-irix4 or iris4
2425 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
2426 Z8000 simulator z8k-zilog-none or z8ksim
2427 Matsushita MN10200 w/simulator mn10200-*-*
2428 H8/500 simulator h8500-hitachi-hms or h8500hms
2429 HP/PA running BSD hppa*-*-bsd*
2430 HP/PA running OSF/1 hppa*-*-osf*
2431 HP/PA Pro target hppa*-*-pro*
2432 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
2433 386BSD i[3456]86-*-bsd*
2434 Sequent family i[3456]86-sequent-sysv4*
2435 i[3456]86-sequent-sysv*
2436 i[3456]86-sequent-bsd*
2437 SPARC running LynxOS sparc-*-lynxos*
2438 SPARC running SunOS 4 sparc-*-sunos4*
2439 Tsqware Sparclet sparclet-*-*
2440 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
2442 *** Changes in GDB 6.0:
2446 Support for debugging the Objective-C programming language has been
2447 integrated into GDB.
2449 * New backtrace mechanism (includes DWARF 2 Call Frame Information).
2451 DWARF 2's Call Frame Information makes available compiler generated
2452 information that more exactly describes the program's run-time stack.
2453 By using this information, GDB is able to provide more robust stack
2456 The i386, amd64 (nee, x86-64), Alpha, m68hc11, ia64, and m32r targets
2457 have been updated to use a new backtrace mechanism which includes
2458 DWARF 2 CFI support.
2462 GDB's remote protocol has been extended to include support for hosted
2463 file I/O (where the remote target uses GDB's file system). See GDB's
2464 remote protocol documentation for details.
2466 * All targets using the new architecture framework.
2468 All of GDB's targets have been updated to use the new internal
2469 architecture framework. The way is now open for future GDB releases
2470 to include cross-architecture native debugging support (i386 on amd64,
2473 * GNU/Linux's Thread Local Storage (TLS)
2475 GDB now includes support for for the GNU/Linux implementation of
2476 per-thread variables.
2478 * GNU/Linux's Native POSIX Thread Library (NPTL)
2480 GDB's thread code has been updated to work with either the new
2481 GNU/Linux NPTL thread library or the older "LinuxThreads" library.
2483 * Separate debug info.
2485 GDB, in conjunction with BINUTILS, now supports a mechanism for
2486 automatically loading debug information from a separate file. Instead
2487 of shipping full debug and non-debug versions of system libraries,
2488 system integrators can now instead ship just the stripped libraries
2489 and optional debug files.
2491 * DWARF 2 Location Expressions
2493 DWARF 2 Location Expressions allow the compiler to more completely
2494 describe the location of variables (even in optimized code) to the
2497 GDB now includes preliminary support for location expressions (support
2498 for DW_OP_piece is still missing).
2502 A number of long standing bugs that caused GDB to die while starting a
2503 Java application have been fixed. GDB's Java support is now
2504 considered "useable".
2506 * GNU/Linux support for fork, vfork, and exec.
2508 The "catch fork", "catch exec", "catch vfork", and "set follow-fork-mode"
2509 commands are now implemented for GNU/Linux. They require a 2.5.x or later
2512 * GDB supports logging output to a file
2514 There are two new commands, "set logging" and "show logging", which can be
2515 used to capture GDB's output to a file.
2517 * The meaning of "detach" has changed for gdbserver
2519 The "detach" command will now resume the application, as documented. To
2520 disconnect from gdbserver and leave it stopped, use the new "disconnect"
2523 * d10v, m68hc11 `regs' command deprecated
2525 The `info registers' command has been updated so that it displays the
2526 registers using a format identical to the old `regs' command.
2530 A new command, "maint set profile on/off", has been added. This command can
2531 be used to enable or disable profiling while running GDB, to profile a
2532 session or a set of commands. In addition there is a new configure switch,
2533 "--enable-profiling", which will cause GDB to be compiled with profiling
2534 data, for more informative profiling results.
2536 * Default MI syntax changed to "mi2".
2538 The default MI (machine interface) syntax, enabled by the command line
2539 option "-i=mi", has been changed to "mi2". The previous MI syntax,
2540 "mi1", can be enabled by specifying the option "-i=mi1".
2542 Support for the original "mi0" syntax (included in GDB 5.0) has been
2545 Fix for gdb/192: removed extraneous space when displaying frame level.
2546 Fix for gdb/672: update changelist is now output in mi list format.
2547 Fix for gdb/702: a -var-assign that updates the value now shows up
2548 in a subsequent -var-update.
2550 * New native configurations.
2552 FreeBSD/amd64 x86_64-*-freebsd*
2554 * Multi-arched targets.
2556 HP/PA HPUX11 hppa*-*-hpux*
2557 Renesas M32R/D w/simulator m32r-*-elf*
2559 * OBSOLETE configurations and files
2561 Configurations that have been declared obsolete in this release have
2562 been commented out. Unless there is activity to revive these
2563 configurations, the next release of GDB will have their sources
2564 permanently REMOVED.
2566 Z8000 simulator z8k-zilog-none or z8ksim
2567 Matsushita MN10200 w/simulator mn10200-*-*
2568 H8/500 simulator h8500-hitachi-hms or h8500hms
2569 HP/PA running BSD hppa*-*-bsd*
2570 HP/PA running OSF/1 hppa*-*-osf*
2571 HP/PA Pro target hppa*-*-pro*
2572 PMAX (MIPS) running Mach 3.0 mips*-*-mach3*
2573 Sequent family i[3456]86-sequent-sysv4*
2574 i[3456]86-sequent-sysv*
2575 i[3456]86-sequent-bsd*
2576 Tsqware Sparclet sparclet-*-*
2577 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
2579 * REMOVED configurations and files
2582 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
2583 IBM AIX PS/2 i[3456]86-*-aix
2584 i386 running Mach 3.0 i[3456]86-*-mach3*
2585 i386 running Mach i[3456]86-*-mach*
2586 i386 running OSF/1 i[3456]86-*osf1mk*
2587 HP/Apollo 68k Family m68*-apollo*-sysv*,
2589 m68*-hp-bsd*, m68*-hp-hpux*
2590 Argonaut Risc Chip (ARC) arc-*-*
2591 Mitsubishi D30V d30v-*-*
2592 Fujitsu FR30 fr30-*-elf*
2593 OS/9000 i[34]86-*-os9k
2594 I960 with MON960 i960-*-coff
2596 * MIPS $fp behavior changed
2598 The convenience variable $fp, for the MIPS, now consistently returns
2599 the address of the current frame's base. Previously, depending on the
2600 context, $fp could refer to either $sp or the current frame's base
2601 address. See ``8.10 Registers'' in the manual ``Debugging with GDB:
2602 The GNU Source-Level Debugger''.
2604 *** Changes in GDB 5.3:
2606 * GNU/Linux shared library multi-threaded performance improved.
2608 When debugging a multi-threaded application on GNU/Linux, GDB now uses
2609 `/proc', in preference to `ptrace' for memory reads. This may result
2610 in an improvement in the start-up time of multi-threaded, shared
2611 library applications when run under GDB. One GDB user writes: ``loads
2612 shared libs like mad''.
2614 * ``gdbserver'' now supports multi-threaded applications on some targets
2616 Support for debugging multi-threaded applications which use
2617 the GNU/Linux LinuxThreads package has been added for
2618 arm*-*-linux*-gnu*, i[3456]86-*-linux*-gnu*, mips*-*-linux*-gnu*,
2619 powerpc*-*-linux*-gnu*, and sh*-*-linux*-gnu*.
2621 * GDB now supports C/C++ preprocessor macros.
2623 GDB now expands preprocessor macro invocations in C/C++ expressions,
2624 and provides various commands for showing macro definitions and how
2627 The new command `macro expand EXPRESSION' expands any macro
2628 invocations in expression, and shows the result.
2630 The new command `show macro MACRO-NAME' shows the definition of the
2631 macro named MACRO-NAME, and where it was defined.
2633 Most compilers don't include information about macros in the debugging
2634 information by default. In GCC 3.1, for example, you need to compile
2635 your program with the options `-gdwarf-2 -g3'. If the macro
2636 information is present in the executable, GDB will read it.
2638 * Multi-arched targets.
2640 DEC Alpha (partial) alpha*-*-*
2641 DEC VAX (partial) vax-*-*
2643 National Semiconductor NS32000 (partial) ns32k-*-*
2644 Motorola 68000 (partial) m68k-*-*
2645 Motorola MCORE mcore-*-*
2649 Fujitsu FRV architecture added by Red Hat frv*-*-*
2652 * New native configurations
2654 Alpha NetBSD alpha*-*-netbsd*
2655 SH NetBSD sh*-*-netbsdelf*
2656 MIPS NetBSD mips*-*-netbsd*
2657 UltraSPARC NetBSD sparc64-*-netbsd*
2659 * OBSOLETE configurations and files
2661 Configurations that have been declared obsolete in this release have
2662 been commented out. Unless there is activity to revive these
2663 configurations, the next release of GDB will have their sources
2664 permanently REMOVED.
2666 Mitsubishi D30V d30v-*-*
2667 OS/9000 i[34]86-*-os9k
2668 IBM AIX PS/2 i[3456]86-*-aix
2669 Fujitsu FR30 fr30-*-elf*
2670 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
2671 Argonaut Risc Chip (ARC) arc-*-*
2672 i386 running Mach 3.0 i[3456]86-*-mach3*
2673 i386 running Mach i[3456]86-*-mach*
2674 i386 running OSF/1 i[3456]86-*osf1mk*
2675 HP/Apollo 68k Family m68*-apollo*-sysv*,
2677 m68*-hp-bsd*, m68*-hp-hpux*
2678 I960 with MON960 i960-*-coff
2680 * OBSOLETE languages
2682 CHILL, a Pascal like language used by telecommunications companies.
2684 * REMOVED configurations and files
2686 AMD 29k family via UDI a29k-amd-udi, udi29k
2687 A29K VxWorks a29k-*-vxworks
2688 AMD 29000 embedded, using EBMON a29k-none-none
2689 AMD 29000 embedded with COFF a29k-none-coff
2690 AMD 29000 embedded with a.out a29k-none-aout
2692 testsuite/gdb.hp/gdb.threads-hp/ directory
2694 * New command "set max-user-call-depth <nnn>"
2696 This command allows the user to limit the call depth of user-defined
2697 commands. The default is 1024.
2699 * Changes in FreeBSD/i386 native debugging.
2701 Support for the "generate-core-file" has been added.
2703 * New commands "dump", "append", and "restore".
2705 These commands allow data to be copied from target memory
2706 to a bfd-format or binary file (dump and append), and back
2707 from a file into memory (restore).
2709 * Improved "next/step" support on multi-processor Alpha Tru64.
2711 The previous single-step mechanism could cause unpredictable problems,
2712 including the random appearance of SIGSEGV or SIGTRAP signals. The use
2713 of a software single-step mechanism prevents this.
2715 *** Changes in GDB 5.2.1:
2723 gdb/182: gdb/323: gdb/237: On alpha, gdb was reporting:
2724 mdebugread.c:2443: gdb-internal-error: sect_index_data not initialized
2725 Fix, by Joel Brobecker imported from mainline.
2727 gdb/439: gdb/291: On some ELF object files, gdb was reporting:
2728 dwarf2read.c:1072: gdb-internal-error: sect_index_text not initialize
2729 Fix, by Fred Fish, imported from mainline.
2731 Dwarf2 .debug_frame & .eh_frame handler improved in many ways.
2732 Surprisingly enough, it works now.
2733 By Michal Ludvig, imported from mainline.
2735 i386 hardware watchpoint support:
2736 avoid misses on second run for some targets.
2737 By Pierre Muller, imported from mainline.
2739 *** Changes in GDB 5.2:
2741 * New command "set trust-readonly-sections on[off]".
2743 This command is a hint that tells gdb that read-only sections
2744 really are read-only (ie. that their contents will not change).
2745 In this mode, gdb will go to the object file rather than the
2746 target to read memory from read-only sections (such as ".text").
2747 This can be a significant performance improvement on some
2748 (notably embedded) targets.
2750 * New command "generate-core-file" (or "gcore").
2752 This new gdb command allows the user to drop a core file of the child
2753 process state at any time. So far it's been implemented only for
2754 GNU/Linux and Solaris, but should be relatively easily ported to other
2755 hosts. Argument is core file name (defaults to core.<pid>).
2757 * New command line option
2759 GDB now accepts --pid or -p followed by a process id.
2761 * Change in command line behavior -- corefiles vs. process ids.
2763 There is a subtle behavior in the way in which GDB handles
2764 command line arguments. The first non-flag argument is always
2765 a program to debug, but the second non-flag argument may either
2766 be a corefile or a process id. Previously, GDB would attempt to
2767 open the second argument as a corefile, and if that failed, would
2768 issue a superfluous error message and then attempt to attach it as
2769 a process. Now, if the second argument begins with a non-digit,
2770 it will be treated as a corefile. If it begins with a digit,
2771 GDB will attempt to attach it as a process, and if no such process
2772 is found, will then attempt to open it as a corefile.
2774 * Changes in ARM configurations.
2776 Multi-arch support is enabled for all ARM configurations. The ARM/NetBSD
2777 configuration is fully multi-arch.
2779 * New native configurations
2781 ARM NetBSD arm*-*-netbsd*
2782 x86 OpenBSD i[3456]86-*-openbsd*
2783 AMD x86-64 running GNU/Linux x86_64-*-linux-*
2784 Sparc64 running FreeBSD sparc64-*-freebsd*
2788 Sanyo XStormy16 xstormy16-elf
2790 * OBSOLETE configurations and files
2792 Configurations that have been declared obsolete in this release have
2793 been commented out. Unless there is activity to revive these
2794 configurations, the next release of GDB will have their sources
2795 permanently REMOVED.
2797 AMD 29k family via UDI a29k-amd-udi, udi29k
2798 A29K VxWorks a29k-*-vxworks
2799 AMD 29000 embedded, using EBMON a29k-none-none
2800 AMD 29000 embedded with COFF a29k-none-coff
2801 AMD 29000 embedded with a.out a29k-none-aout
2803 testsuite/gdb.hp/gdb.threads-hp/ directory
2805 * REMOVED configurations and files
2807 TI TMS320C80 tic80-*-*
2809 PowerPC Solaris powerpcle-*-solaris*
2810 PowerPC Windows NT powerpcle-*-cygwin32
2811 PowerPC Netware powerpc-*-netware*
2812 Harris/CXUX m88k m88*-harris-cxux*
2813 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
2814 ns32k-utek-sysv* ns32k-utek-*
2815 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
2816 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
2817 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
2818 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
2819 Apple Macintosh (MPW) host and target N/A host, powerpc-*-macos*
2821 * Changes to command line processing
2823 The new `--args' feature can be used to specify command-line arguments
2824 for the inferior from gdb's command line.
2826 * Changes to key bindings
2828 There is a new `operate-and-get-next' function bound to `C-o'.
2830 *** Changes in GDB 5.1.1
2832 Fix compile problem on DJGPP.
2834 Fix a problem with floating-point registers on the i386 being
2837 Fix to stop GDB crashing on .debug_str debug info.
2839 Numerous documentation fixes.
2841 Numerous testsuite fixes.
2843 *** Changes in GDB 5.1:
2845 * New native configurations
2847 Alpha FreeBSD alpha*-*-freebsd*
2848 x86 FreeBSD 3.x and 4.x i[3456]86*-freebsd[34]*
2849 MIPS GNU/Linux mips*-*-linux*
2850 MIPS SGI Irix 6.x mips*-sgi-irix6*
2851 ia64 AIX ia64-*-aix*
2852 s390 and s390x GNU/Linux {s390,s390x}-*-linux*
2856 Motorola 68HC11 and 68HC12 m68hc11-elf
2858 UltraSparc running GNU/Linux sparc64-*-linux*
2860 * OBSOLETE configurations and files
2862 x86 FreeBSD before 2.2 i[3456]86*-freebsd{1,2.[01]}*,
2863 Harris/CXUX m88k m88*-harris-cxux*
2864 Most ns32k hosts and targets ns32k-*-mach3* ns32k-umax-*
2865 ns32k-utek-sysv* ns32k-utek-*
2866 TI TMS320C80 tic80-*-*
2868 Ultracomputer (29K) running Sym1 a29k-nyu-sym1 a29k-*-kern*
2869 PowerPC Solaris powerpcle-*-solaris*
2870 PowerPC Windows NT powerpcle-*-cygwin32
2871 PowerPC Netware powerpc-*-netware*
2872 SunOS 4.0.Xi on i386 i[3456]86-*-sunos*
2873 Sony NEWS (68K) running NEWSOS 3.x m68*-sony-sysv news
2874 ISI Optimum V (3.05) under 4.3bsd. m68*-isi-*
2875 Apple Macintosh (MPW) host N/A
2877 stuff.c (Program to stuff files into a specially prepared space in kdb)
2878 kdb-start.c (Main loop for the standalone kernel debugger)
2880 Configurations that have been declared obsolete in this release have
2881 been commented out. Unless there is activity to revive these
2882 configurations, the next release of GDB will have their sources
2883 permanently REMOVED.
2885 * REMOVED configurations and files
2887 Altos 3068 m68*-altos-*
2888 Convex c1-*-*, c2-*-*
2890 ARM RISCix arm-*-* (as host)
2894 * GDB has been converted to ISO C.
2896 GDB's source code has been converted to ISO C. In particular, the
2897 sources are fully protoized, and rely on standard headers being
2902 * "info symbol" works on platforms which use COFF, ECOFF, XCOFF, and NLM.
2904 * The MI enabled by default.
2906 The new machine oriented interface (MI) introduced in GDB 5.0 has been
2907 revised and enabled by default. Packages which use GDB as a debugging
2908 engine behind a UI or another front end are encouraged to switch to
2909 using the GDB/MI interface, instead of the old annotations interface
2910 which is now deprecated.
2912 * Support for debugging Pascal programs.
2914 GDB now includes support for debugging Pascal programs. The following
2915 main features are supported:
2917 - Pascal-specific data types such as sets;
2919 - automatic recognition of Pascal sources based on file-name
2922 - Pascal-style display of data types, variables, and functions;
2924 - a Pascal expression parser.
2926 However, some important features are not yet supported.
2928 - Pascal string operations are not supported at all;
2930 - there are some problems with boolean types;
2932 - Pascal type hexadecimal constants are not supported
2933 because they conflict with the internal variables format;
2935 - support for Pascal objects and classes is not full yet;
2937 - unlike Pascal, GDB is case-sensitive for symbol names.
2939 * Changes in completion.
2941 Commands such as `shell', `run' and `set args', which pass arguments
2942 to inferior programs, now complete on file names, similar to what
2943 users expect at the shell prompt.
2945 Commands which accept locations, such as `disassemble', `print',
2946 `breakpoint', `until', etc. now complete on filenames as well as
2947 program symbols. Thus, if you type "break foob TAB", and the source
2948 files linked into the programs include `foobar.c', that file name will
2949 be one of the candidates for completion. However, file names are not
2950 considered for completion after you typed a colon that delimits a file
2951 name from a name of a function in that file, as in "break foo.c:bar".
2953 `set demangle-style' completes on available demangling styles.
2955 * New platform-independent commands:
2957 It is now possible to define a post-hook for a command as well as a
2958 hook that runs before the command. For more details, see the
2959 documentation of `hookpost' in the GDB manual.
2961 * Changes in GNU/Linux native debugging.
2963 Support for debugging multi-threaded programs has been completely
2964 revised for all platforms except m68k and sparc. You can now debug as
2965 many threads as your system allows you to have.
2967 Attach/detach is supported for multi-threaded programs.
2969 Support for SSE registers was added for x86. This doesn't work for
2970 multi-threaded programs though.
2972 * Changes in MIPS configurations.
2974 Multi-arch support is enabled for all MIPS configurations.
2976 GDB can now be built as native debugger on SGI Irix 6.x systems for
2977 debugging n32 executables. (Debugging 64-bit executables is not yet
2980 * Unified support for hardware watchpoints in all x86 configurations.
2982 Most (if not all) native x86 configurations support hardware-assisted
2983 breakpoints and watchpoints in a unified manner. This support
2984 implements debug register sharing between watchpoints, which allows to
2985 put a virtually infinite number of watchpoints on the same address,
2986 and also supports watching regions up to 16 bytes with several debug
2989 The new maintenance command `maintenance show-debug-regs' toggles
2990 debugging print-outs in functions that insert, remove, and test
2991 watchpoints and hardware breakpoints.
2993 * Changes in the DJGPP native configuration.
2995 New command ``info dos sysinfo'' displays assorted information about
2996 the CPU, OS, memory, and DPMI server.
2998 New commands ``info dos gdt'', ``info dos ldt'', and ``info dos idt''
2999 display information about segment descriptors stored in GDT, LDT, and
3002 New commands ``info dos pde'' and ``info dos pte'' display entries
3003 from Page Directory and Page Tables (for now works with CWSDPMI only).
3004 New command ``info dos address-pte'' displays the Page Table entry for
3005 a given linear address.
3007 GDB can now pass command lines longer than 126 characters to the
3008 program being debugged (requires an update to the libdbg.a library
3009 which is part of the DJGPP development kit).
3011 DWARF2 debug info is now supported.
3013 It is now possible to `step' and `next' through calls to `longjmp'.
3015 * Changes in documentation.
3017 All GDB documentation was converted to GFDL, the GNU Free
3018 Documentation License.
3020 Tracepoints-related commands are now fully documented in the GDB
3023 TUI, the Text-mode User Interface, is now documented in the manual.
3025 Tracepoints-related commands are now fully documented in the GDB
3028 The "GDB Internals" manual now has an index. It also includes
3029 documentation of `ui_out' functions, GDB coding standards, x86
3030 hardware watchpoints, and memory region attributes.
3032 * GDB's version number moved to ``version.in''
3034 The Makefile variable VERSION has been replaced by the file
3035 ``version.in''. People creating GDB distributions should update the
3036 contents of this file.
3040 GUD support is now a standard part of the EMACS distribution.
3042 *** Changes in GDB 5.0:
3044 * Improved support for debugging FP programs on x86 targets
3046 Unified and much-improved support for debugging floating-point
3047 programs on all x86 targets. In particular, ``info float'' now
3048 displays the FP registers in the same format on all x86 targets, with
3049 greater level of detail.
3051 * Improvements and bugfixes in hardware-assisted watchpoints
3053 It is now possible to watch array elements, struct members, and
3054 bitfields with hardware-assisted watchpoints. Data-read watchpoints
3055 on x86 targets no longer erroneously trigger when the address is
3058 * Improvements in the native DJGPP version of GDB
3060 The distribution now includes all the scripts and auxiliary files
3061 necessary to build the native DJGPP version on MS-DOS/MS-Windows
3062 machines ``out of the box''.
3064 The DJGPP version can now debug programs that use signals. It is
3065 possible to catch signals that happened in the debuggee, deliver
3066 signals to it, interrupt it with Ctrl-C, etc. (Previously, a signal
3067 would kill the program being debugged.) Programs that hook hardware
3068 interrupts (keyboard, timer, etc.) can also be debugged.
3070 It is now possible to debug DJGPP programs that redirect their
3071 standard handles or switch them to raw (as opposed to cooked) mode, or
3072 even close them. The command ``run < foo > bar'' works as expected,
3073 and ``info terminal'' reports useful information about the debuggee's
3074 terminal, including raw/cooked mode, redirection, etc.
3076 The DJGPP version now uses termios functions for console I/O, which
3077 enables debugging graphics programs. Interrupting GDB with Ctrl-C
3080 DOS-style file names with drive letters are now fully supported by
3083 It is now possible to debug DJGPP programs that switch their working
3084 directory. It is also possible to rerun the debuggee any number of
3085 times without restarting GDB; thus, you can use the same setup,
3086 breakpoints, etc. for many debugging sessions.
3088 * New native configurations
3090 ARM GNU/Linux arm*-*-linux*
3091 PowerPC GNU/Linux powerpc-*-linux*
3095 Motorola MCore mcore-*-*
3096 x86 VxWorks i[3456]86-*-vxworks*
3097 PowerPC VxWorks powerpc-*-vxworks*
3098 TI TMS320C80 tic80-*-*
3100 * OBSOLETE configurations
3102 Altos 3068 m68*-altos-*
3103 Convex c1-*-*, c2-*-*
3105 ARM RISCix arm-*-* (as host)
3108 Configurations that have been declared obsolete will be commented out,
3109 but the code will be left in place. If there is no activity to revive
3110 these configurations before the next release of GDB, the sources will
3111 be permanently REMOVED.
3113 * Gould support removed
3115 Support for the Gould PowerNode and NP1 has been removed.
3117 * New features for SVR4
3119 On SVR4 native platforms (such as Solaris), if you attach to a process
3120 without first loading a symbol file, GDB will now attempt to locate and
3121 load symbols from the running process's executable file.
3123 * Many C++ enhancements
3125 C++ support has been greatly improved. Overload resolution now works properly
3126 in almost all cases. RTTI support is on the way.
3128 * Remote targets can connect to a sub-program
3130 A popen(3) style serial-device has been added. This device starts a
3131 sub-process (such as a stand-alone simulator) and then communicates
3132 with that. The sub-program to run is specified using the syntax
3133 ``|<program> <args>'' vis:
3135 (gdb) set remotedebug 1
3136 (gdb) target extended-remote |mn10300-elf-sim program-args
3138 * MIPS 64 remote protocol
3140 A long standing bug in the mips64 remote protocol where by GDB
3141 expected certain 32 bit registers (ex SR) to be transfered as 32
3142 instead of 64 bits has been fixed.
3144 The command ``set remote-mips64-transfers-32bit-regs on'' has been
3145 added to provide backward compatibility with older versions of GDB.
3147 * ``set remotebinarydownload'' replaced by ``set remote X-packet''
3149 The command ``set remotebinarydownload'' command has been replaced by
3150 ``set remote X-packet''. Other commands in ``set remote'' family
3151 include ``set remote P-packet''.
3153 * Breakpoint commands accept ranges.
3155 The breakpoint commands ``enable'', ``disable'', and ``delete'' now
3156 accept a range of breakpoints, e.g. ``5-7''. The tracepoint command
3157 ``tracepoint passcount'' also accepts a range of tracepoints.
3159 * ``apropos'' command added.
3161 The ``apropos'' command searches through command names and
3162 documentation strings, printing out matches, making it much easier to
3163 try to find a command that does what you are looking for.
3167 A new machine oriented interface (MI) has been added to GDB. This
3168 interface is designed for debug environments running GDB as a separate
3169 process. This is part of the long term libGDB project. See the
3170 "GDB/MI" chapter of the GDB manual for further information. It can be
3171 enabled by configuring with:
3173 .../configure --enable-gdbmi
3175 *** Changes in GDB-4.18:
3177 * New native configurations
3179 HP-UX 10.20 hppa*-*-hpux10.20
3180 HP-UX 11.x hppa*-*-hpux11.0*
3181 M68K GNU/Linux m68*-*-linux*
3185 Fujitsu FR30 fr30-*-elf*
3186 Intel StrongARM strongarm-*-*
3187 Mitsubishi D30V d30v-*-*
3189 * OBSOLETE configurations
3191 Gould PowerNode, NP1 np1-*-*, pn-*-*
3193 Configurations that have been declared obsolete will be commented out,
3194 but the code will be left in place. If there is no activity to revive
3195 these configurations before the next release of GDB, the sources will
3196 be permanently REMOVED.
3200 As a compatibility experiment, GDB's source files buildsym.h and
3201 buildsym.c have been converted to pure standard C, no longer
3202 containing any K&R compatibility code. We believe that all systems in
3203 use today either come with a standard C compiler, or have a GCC port
3204 available. If this is not true, please report the affected
3205 configuration to bug-gdb@gnu.org immediately. See the README file for
3206 information about getting a standard C compiler if you don't have one
3211 GDB now uses readline 2.2.
3213 * set extension-language
3215 You can now control the mapping between filename extensions and source
3216 languages by using the `set extension-language' command. For instance,
3217 you can ask GDB to treat .c files as C++ by saying
3218 set extension-language .c c++
3219 The command `info extensions' lists all of the recognized extensions
3220 and their associated languages.
3222 * Setting processor type for PowerPC and RS/6000
3224 When GDB is configured for a powerpc*-*-* or an rs6000*-*-* target,
3225 you can use the `set processor' command to specify what variant of the
3226 PowerPC family you are debugging. The command
3230 sets the PowerPC/RS6000 variant to NAME. GDB knows about the
3231 following PowerPC and RS6000 variants:
3233 ppc-uisa PowerPC UISA - a PPC processor as viewed by user-level code
3234 rs6000 IBM RS6000 ("POWER") architecture, user-level view
3236 403GC IBM PowerPC 403GC
3237 505 Motorola PowerPC 505
3238 860 Motorola PowerPC 860 or 850
3239 601 Motorola PowerPC 601
3240 602 Motorola PowerPC 602
3241 603 Motorola/IBM PowerPC 603 or 603e
3242 604 Motorola PowerPC 604 or 604e
3243 750 Motorola/IBM PowerPC 750 or 750
3245 At the moment, this command just tells GDB what to name the
3246 special-purpose processor registers. Since almost all the affected
3247 registers are inaccessible to user-level programs, this command is
3248 only useful for remote debugging in its present form.
3252 Thanks to a major code donation from Hewlett-Packard, GDB now has much
3253 more extensive support for HP-UX. Added features include shared
3254 library support, kernel threads and hardware watchpoints for 11.00,
3255 support for HP's ANSI C and C++ compilers, and a compatibility mode
3256 for xdb and dbx commands.
3260 HP's donation includes the new concept of catchpoints, which is a
3261 generalization of the old catch command. On HP-UX, it is now possible
3262 to catch exec, fork, and vfork, as well as library loading.
3264 This means that the existing catch command has changed; its first
3265 argument now specifies the type of catch to be set up. See the
3266 output of "help catch" for a list of catchpoint types.
3268 * Debugging across forks
3270 On HP-UX, you can choose which process to debug when a fork() happens
3275 HP has donated a curses-based terminal user interface (TUI). To get
3276 it, build with --enable-tui. Although this can be enabled for any
3277 configuration, at present it only works for native HP debugging.
3279 * GDB remote protocol additions
3281 A new protocol packet 'X' that writes binary data is now available.
3282 Default behavior is to try 'X', then drop back to 'M' if the stub
3283 fails to respond. The settable variable `remotebinarydownload'
3284 allows explicit control over the use of 'X'.
3286 For 64-bit targets, the memory packets ('M' and 'm') can now contain a
3287 full 64-bit address. The command
3289 set remoteaddresssize 32
3291 can be used to revert to the old behaviour. For existing remote stubs
3292 the change should not be noticed, as the additional address information
3295 In order to assist in debugging stubs, you may use the maintenance
3296 command `packet' to send any text string to the stub. For instance,
3298 maint packet heythere
3300 sends the packet "$heythere#<checksum>". Note that it is very easy to
3301 disrupt a debugging session by sending the wrong packet at the wrong
3304 The compare-sections command allows you to compare section data on the
3305 target to what is in the executable file without uploading or
3306 downloading, by comparing CRC checksums.
3308 * Tracing can collect general expressions
3310 You may now collect general expressions at tracepoints. This requires
3311 further additions to the target-side stub; see tracepoint.c and
3312 doc/agentexpr.texi for further details.
3314 * mask-address variable for Mips
3316 For Mips targets, you may control the zeroing of the upper 32 bits of
3317 a 64-bit address by entering `set mask-address on'. This is mainly
3318 of interest to users of embedded R4xxx and R5xxx processors.
3320 * Higher serial baud rates
3322 GDB's serial code now allows you to specify baud rates 57600, 115200,
3323 230400, and 460800 baud. (Note that your host system may not be able
3324 to achieve all of these rates.)
3328 The i960 configuration now includes an initial implementation of a
3329 builtin simulator, contributed by Jim Wilson.
3332 *** Changes in GDB-4.17:
3334 * New native configurations
3336 Alpha GNU/Linux alpha*-*-linux*
3337 Unixware 2.x i[3456]86-unixware2*
3338 Irix 6.x mips*-sgi-irix6*
3339 PowerPC GNU/Linux powerpc-*-linux*
3340 PowerPC Solaris powerpcle-*-solaris*
3341 Sparc GNU/Linux sparc-*-linux*
3342 Motorola sysV68 R3V7.1 m68k-motorola-sysv
3346 Argonaut Risc Chip (ARC) arc-*-*
3347 Hitachi H8/300S h8300*-*-*
3348 Matsushita MN10200 w/simulator mn10200-*-*
3349 Matsushita MN10300 w/simulator mn10300-*-*
3350 MIPS NEC VR4100 mips64*vr4100*{,el}-*-elf*
3351 MIPS NEC VR5000 mips64*vr5000*{,el}-*-elf*
3352 MIPS Toshiba TX39 mips64*tx39*{,el}-*-elf*
3353 Mitsubishi D10V w/simulator d10v-*-*
3354 Mitsubishi M32R/D w/simulator m32r-*-elf*
3355 Tsqware Sparclet sparclet-*-*
3356 NEC V850 w/simulator v850-*-*
3358 * New debugging protocols
3360 ARM with RDI protocol arm*-*-*
3361 M68K with dBUG monitor m68*-*-{aout,coff,elf}
3362 DDB and LSI variants of PMON protocol mips*-*-*
3363 PowerPC with DINK32 monitor powerpc{,le}-*-eabi
3364 PowerPC with SDS protocol powerpc{,le}-*-eabi
3365 Macraigor OCD (Wiggler) devices powerpc{,le}-*-eabi
3369 All configurations can now understand and use the DWARF 2 debugging
3370 format. The choice is automatic, if the symbol file contains DWARF 2
3375 GDB now includes basic Java language support. This support is
3376 only useful with Java compilers that produce native machine code.
3378 * solib-absolute-prefix and solib-search-path
3380 For SunOS and SVR4 shared libraries, you may now set the prefix for
3381 loading absolute shared library symbol files, and the search path for
3382 locating non-absolute shared library symbol files.
3384 * Live range splitting
3386 GDB can now effectively debug code for which GCC has performed live
3387 range splitting as part of its optimization. See gdb/doc/LRS for
3388 more details on the expected format of the stabs information.
3392 GDB's support for the GNU Hurd, including thread debugging, has been
3393 updated to work with current versions of the Hurd.
3397 GDB's ARM target configuration now handles the ARM7T (Thumb) 16-bit
3398 instruction set. ARM GDB automatically detects when Thumb
3399 instructions are in use, and adjusts disassembly and backtracing
3404 GDB's MIPS target configurations now handle the MIP16 16-bit
3409 GDB now includes support for overlays; if an executable has been
3410 linked such that multiple sections are based at the same address, GDB
3411 will decide which section to use for symbolic info. You can choose to
3412 control the decision manually, using overlay commands, or implement
3413 additional target-side support and use "overlay load-target" to bring
3414 in the overlay mapping. Do "help overlay" for more detail.
3418 The command "info symbol <address>" displays information about
3419 the symbol at the specified address.
3423 The standard remote protocol now includes an extension that allows
3424 asynchronous collection and display of trace data. This requires
3425 extensive support in the target-side debugging stub. Tracing mode
3426 includes a new interaction mode in GDB and new commands: see the
3427 file tracepoint.c for more details.
3431 Configurations for embedded MIPS now include a simulator contributed
3432 by Cygnus Solutions. The simulator supports the instruction sets
3433 of most MIPS variants.
3437 Sparc configurations may now include the ERC32 simulator contributed
3438 by the European Space Agency. The simulator is not built into
3439 Sparc targets by default; configure with --enable-sim to include it.
3443 For target configurations that may include multiple variants of a
3444 basic architecture (such as MIPS and SH), you may now set the
3445 architecture explicitly. "set arch" sets, "info arch" lists
3446 the possible architectures.
3448 *** Changes in GDB-4.16:
3450 * New native configurations
3452 Windows 95, x86 Windows NT i[345]86-*-cygwin32
3453 M68K NetBSD m68k-*-netbsd*
3454 PowerPC AIX 4.x powerpc-*-aix*
3455 PowerPC MacOS powerpc-*-macos*
3456 PowerPC Windows NT powerpcle-*-cygwin32
3457 RS/6000 AIX 4.x rs6000-*-aix4*
3461 ARM with RDP protocol arm-*-*
3462 I960 with MON960 i960-*-coff
3463 MIPS VxWorks mips*-*-vxworks*
3464 MIPS VR4300 with PMON mips64*vr4300{,el}-*-elf*
3465 PowerPC with PPCBUG monitor powerpc{,le}-*-eabi*
3467 Matra Sparclet sparclet-*-*
3471 The powerpc-eabi configuration now includes the PSIM simulator,
3472 contributed by Andrew Cagney, with assistance from Mike Meissner.
3473 PSIM is a very elaborate model of the PowerPC, including not only
3474 basic instruction set execution, but also details of execution unit
3475 performance and I/O hardware. See sim/ppc/README for more details.
3479 GDB now works with Solaris 2.5.
3481 * Windows 95/NT native
3483 GDB will now work as a native debugger on Windows 95 and Windows NT.
3484 To build it from source, you must use the "gnu-win32" environment,
3485 which uses a DLL to emulate enough of Unix to run the GNU tools.
3486 Further information, binaries, and sources are available at
3487 ftp.cygnus.com, under pub/gnu-win32.
3489 * dont-repeat command
3491 If a user-defined command includes the command `dont-repeat', then the
3492 command will not be repeated if the user just types return. This is
3493 useful if the command is time-consuming to run, so that accidental
3494 extra keystrokes don't run the same command many times.
3496 * Send break instead of ^C
3498 The standard remote protocol now includes an option to send a break
3499 rather than a ^C to the target in order to interrupt it. By default,
3500 GDB will send ^C; to send a break, set the variable `remotebreak' to 1.
3502 * Remote protocol timeout
3504 The standard remote protocol includes a new variable `remotetimeout'
3505 that allows you to set the number of seconds before GDB gives up trying
3506 to read from the target. The default value is 2.
3508 * Automatic tracking of dynamic object loading (HPUX and Solaris only)
3510 By default GDB will automatically keep track of objects as they are
3511 loaded and unloaded by the dynamic linker. By using the command `set
3512 stop-on-solib-events 1' you can arrange for GDB to stop the inferior
3513 when shared library events occur, thus allowing you to set breakpoints
3514 in shared libraries which are explicitly loaded by the inferior.
3516 Note this feature does not work on hpux8. On hpux9 you must link
3517 /usr/lib/end.o into your program. This feature should work
3518 automatically on hpux10.
3520 * Irix 5.x hardware watchpoint support
3522 Irix 5 configurations now support the use of hardware watchpoints.
3524 * Mips protocol "SYN garbage limit"
3526 When debugging a Mips target using the `target mips' protocol, you
3527 may set the number of characters that GDB will ignore by setting
3528 the `syn-garbage-limit'. A value of -1 means that GDB will ignore
3529 every character. The default value is 1050.
3531 * Recording and replaying remote debug sessions
3533 If you set `remotelogfile' to the name of a file, gdb will write to it
3534 a recording of a remote debug session. This recording may then be
3535 replayed back to gdb using "gdbreplay". See gdbserver/README for
3536 details. This is useful when you have a problem with GDB while doing
3537 remote debugging; you can make a recording of the session and send it
3538 to someone else, who can then recreate the problem.
3540 * Speedups for remote debugging
3542 GDB includes speedups for downloading and stepping MIPS systems using
3543 the IDT monitor, fast downloads to the Hitachi SH E7000 emulator,
3544 and more efficient S-record downloading.
3546 * Memory use reductions and statistics collection
3548 GDB now uses less memory and reports statistics about memory usage.
3549 Try the `maint print statistics' command, for example.
3551 *** Changes in GDB-4.15:
3553 * Psymtabs for XCOFF
3555 The symbol reader for AIX GDB now uses partial symbol tables. This
3556 can greatly improve startup time, especially for large executables.
3558 * Remote targets use caching
3560 Remote targets now use a data cache to speed up communication with the
3561 remote side. The data cache could lead to incorrect results because
3562 it doesn't know about volatile variables, thus making it impossible to
3563 debug targets which use memory mapped I/O devices. `set remotecache
3564 off' turns the the data cache off.
3566 * Remote targets may have threads
3568 The standard remote protocol now includes support for multiple threads
3569 in the target system, using new protocol commands 'H' and 'T'. See
3570 gdb/remote.c for details.
3574 If GDB is configured with `--enable-netrom', then it will include
3575 support for the NetROM ROM emulator from XLNT Designs. The NetROM
3576 acts as though it is a bank of ROM on the target board, but you can
3577 write into it over the network. GDB's support consists only of
3578 support for fast loading into the emulated ROM; to debug, you must use
3579 another protocol, such as standard remote protocol. The usual
3580 sequence is something like
3582 target nrom <netrom-hostname>
3584 target remote <netrom-hostname>:1235
3588 GDB now includes support for the Apple Macintosh, as a host only. It
3589 may be run as either an MPW tool or as a standalone application, and
3590 it can debug through the serial port. All the usual GDB commands are
3591 available, but to the target command, you must supply "serial" as the
3592 device type instead of "/dev/ttyXX". See mpw-README in the main
3593 directory for more information on how to build. The MPW configuration
3594 scripts */mpw-config.in support only a few targets, and only the
3595 mips-idt-ecoff target has been tested.
3599 GDB configuration now uses autoconf. This is not user-visible,
3600 but does simplify configuration and building.
3604 GDB now supports hpux10.
3606 *** Changes in GDB-4.14:
3608 * New native configurations
3610 x86 FreeBSD i[345]86-*-freebsd
3611 x86 NetBSD i[345]86-*-netbsd
3612 NS32k NetBSD ns32k-*-netbsd
3613 Sparc NetBSD sparc-*-netbsd
3617 A29K VxWorks a29k-*-vxworks
3618 HP PA PRO embedded (WinBond W89K & Oki OP50N) hppa*-*-pro*
3619 CPU32 EST-300 emulator m68*-*-est*
3620 PowerPC ELF powerpc-*-elf
3623 * Alpha OSF/1 support for procfs
3625 GDB now supports procfs under OSF/1-2.x and higher, which makes it
3626 possible to attach to running processes. As the mounting of the /proc
3627 filesystem is optional on the Alpha, GDB automatically determines
3628 the availability of /proc during startup. This can lead to problems
3629 if /proc is unmounted after GDB has been started.
3631 * Arguments to user-defined commands
3633 User commands may accept up to 10 arguments separated by whitespace.
3634 Arguments are accessed within the user command via $arg0..$arg9. A
3637 print $arg0 + $arg1 + $arg2
3639 To execute the command use:
3642 Defines the command "adder" which prints the sum of its three arguments.
3643 Note the arguments are text substitutions, so they may reference variables,
3644 use complex expressions, or even perform inferior function calls.
3646 * New `if' and `while' commands
3648 This makes it possible to write more sophisticated user-defined
3649 commands. Both commands take a single argument, which is the
3650 expression to evaluate, and must be followed by the commands to
3651 execute, one per line, if the expression is nonzero, the list being
3652 terminated by the word `end'. The `if' command list may include an
3653 `else' word, which causes the following commands to be executed only
3654 if the expression is zero.
3656 * Fortran source language mode
3658 GDB now includes partial support for Fortran 77. It will recognize
3659 Fortran programs and can evaluate a subset of Fortran expressions, but
3660 variables and functions may not be handled correctly. GDB will work
3661 with G77, but does not yet know much about symbols emitted by other
3664 * Better HPUX support
3666 Most debugging facilities now work on dynamic executables for HPPAs
3667 running hpux9 or later. You can attach to running dynamically linked
3668 processes, but by default the dynamic libraries will be read-only, so
3669 for instance you won't be able to put breakpoints in them. To change
3670 that behavior do the following before running the program:
3676 This will cause the libraries to be mapped private and read-write.
3677 To revert to the normal behavior, do this:
3683 You cannot set breakpoints or examine data in the library until after
3684 the library is loaded if the function/data symbols do not have
3687 GDB can now also read debug symbols produced by the HP C compiler on
3688 HPPAs (sorry, no C++, Fortran or 68k support).
3690 * Target byte order now dynamically selectable
3692 You can choose which byte order to use with a target system, via the
3693 commands "set endian big" and "set endian little", and you can see the
3694 current setting by using "show endian". You can also give the command
3695 "set endian auto", in which case GDB will use the byte order
3696 associated with the executable. Currently, only embedded MIPS
3697 configurations support dynamic selection of target byte order.
3699 * New DOS host serial code
3701 This version uses DPMI interrupts to handle buffered I/O, so you
3702 no longer need to run asynctsr when debugging boards connected to
3705 *** Changes in GDB-4.13:
3707 * New "complete" command
3709 This lists all the possible completions for the rest of the line, if it
3710 were to be given as a command itself. This is intended for use by emacs.
3712 * Trailing space optional in prompt
3714 "set prompt" no longer adds a space for you after the prompt you set. This
3715 allows you to set a prompt which ends in a space or one that does not.
3717 * Breakpoint hit counts
3719 "info break" now displays a count of the number of times the breakpoint
3720 has been hit. This is especially useful in conjunction with "ignore"; you
3721 can ignore a large number of breakpoint hits, look at the breakpoint info
3722 to see how many times the breakpoint was hit, then run again, ignoring one
3723 less than that number, and this will get you quickly to the last hit of
3726 * Ability to stop printing at NULL character
3728 "set print null-stop" will cause GDB to stop printing the characters of
3729 an array when the first NULL is encountered. This is useful when large
3730 arrays actually contain only short strings.
3732 * Shared library breakpoints
3734 In SunOS 4.x, SVR4, and Alpha OSF/1 configurations, you can now set
3735 breakpoints in shared libraries before the executable is run.
3737 * Hardware watchpoints
3739 There is a new hardware breakpoint for the watch command for sparclite
3740 targets. See gdb/sparclite/hw_breakpoint.note.
3742 Hardware watchpoints are also now supported under GNU/Linux.
3746 Annotations have been added. These are for use with graphical interfaces,
3747 and are still experimental. Currently only gdba.el uses these.
3749 * Improved Irix 5 support
3751 GDB now works properly with Irix 5.2.
3753 * Improved HPPA support
3755 GDB now works properly with the latest GCC and GAS.
3757 * New native configurations
3759 Sequent PTX4 i[34]86-sequent-ptx4
3760 HPPA running OSF/1 hppa*-*-osf*
3761 Atari TT running SVR4 m68*-*-sysv4*
3762 RS/6000 LynxOS rs6000-*-lynxos*
3766 OS/9000 i[34]86-*-os9k
3767 MIPS R4000 mips64*{,el}-*-{ecoff,elf}
3770 * Hitachi SH7000 and E7000-PC ICE support
3772 There is now support for communicating with the Hitachi E7000-PC ICE.
3773 This is available automatically when GDB is configured for the SH.
3777 As usual, a variety of small fixes and improvements, both generic
3778 and configuration-specific. See the ChangeLog for more detail.
3780 *** Changes in GDB-4.12:
3782 * Irix 5 is now supported
3786 GDB-4.12 on the HPPA has a number of changes which make it unable
3787 to debug the output from the currently released versions of GCC and
3788 GAS (GCC 2.5.8 and GAS-2.2 or PAGAS-1.36). Until the next major release
3789 of GCC and GAS, versions of these tools designed to work with GDB-4.12
3790 can be retrieved via anonymous ftp from jaguar.cs.utah.edu:/dist.
3793 *** Changes in GDB-4.11:
3795 * User visible changes:
3799 The "set remotedebug" option is now consistent between the mips remote
3800 target, remote targets using the gdb-specific protocol, UDI (AMD's
3801 debug protocol for the 29k) and the 88k bug monitor. It is now an
3802 integer specifying a debug level (normally 0 or 1, but 2 means more
3803 debugging info for the mips target).
3805 * DEC Alpha native support
3807 GDB now works on the DEC Alpha. GCC 2.4.5 does not produce usable
3808 debug info, but GDB works fairly well with the DEC compiler and should
3809 work with a future GCC release. See the README file for a few
3810 Alpha-specific notes.
3812 * Preliminary thread implementation
3814 GDB now has preliminary thread support for both SGI/Irix and LynxOS.
3816 * LynxOS native and target support for 386
3818 This release has been hosted on LynxOS 2.2, and also can be configured
3819 to remotely debug programs running under LynxOS (see gdb/gdbserver/README
3822 * Improvements in C++ mangling/demangling.
3824 This release has much better g++ debugging, specifically in name
3825 mangling/demangling, virtual function calls, print virtual table,
3826 call methods, ...etc.
3828 *** Changes in GDB-4.10:
3830 * User visible changes:
3832 Remote debugging using the GDB-specific (`target remote') protocol now
3833 supports the `load' command. This is only useful if you have some
3834 other way of getting the stub to the target system, and you can put it
3835 somewhere in memory where it won't get clobbered by the download.
3837 Filename completion now works.
3839 When run under emacs mode, the "info line" command now causes the
3840 arrow to point to the line specified. Also, "info line" prints
3841 addresses in symbolic form (as well as hex).
3843 All vxworks based targets now support a user settable option, called
3844 vxworks-timeout. This option represents the number of seconds gdb
3845 should wait for responses to rpc's. You might want to use this if
3846 your vxworks target is, perhaps, a slow software simulator or happens
3847 to be on the far side of a thin network line.
3851 This release contains support for using a DEC alpha as a GDB host for
3852 cross debugging. Native alpha debugging is not supported yet.
3855 *** Changes in GDB-4.9:
3859 This is the first GDB release which is accompanied by a matching testsuite.
3860 The testsuite requires installation of dejagnu, which should be available
3861 via ftp from most sites that carry GNU software.
3865 'Cfront' style demangling has had its name changed to 'ARM' style, to
3866 emphasize that it was written from the specifications in the C++ Annotated
3867 Reference Manual, not necessarily to be compatible with AT&T cfront. Despite
3868 disclaimers, it still generated too much confusion with users attempting to
3869 use gdb with AT&T cfront.
3873 GDB now uses a standard remote interface to a simulator library.
3874 So far, the library contains simulators for the Zilog Z8001/2, the
3875 Hitachi H8/300, H8/500 and Super-H.
3877 * New targets supported
3879 H8/300 simulator h8300-hitachi-hms or h8300hms
3880 H8/500 simulator h8500-hitachi-hms or h8500hms
3881 SH simulator sh-hitachi-hms or sh
3882 Z8000 simulator z8k-zilog-none or z8ksim
3883 IDT MIPS board over serial line mips-idt-ecoff
3885 Cross-debugging to GO32 targets is supported. It requires a custom
3886 version of the i386-stub.c module which is integrated with the
3887 GO32 memory extender.
3889 * New remote protocols
3891 MIPS remote debugging protocol.
3893 * New source languages supported
3895 This version includes preliminary support for Chill, a Pascal like language
3896 used by telecommunications companies. Chill support is also being integrated
3897 into the GNU compiler, but we don't know when it will be publically available.
3900 *** Changes in GDB-4.8:
3902 * HP Precision Architecture supported
3904 GDB now supports HP PA-RISC machines running HPUX. A preliminary
3905 version of this support was available as a set of patches from the
3906 University of Utah. GDB does not support debugging of programs
3907 compiled with the HP compiler, because HP will not document their file
3908 format. Instead, you must use GCC (version 2.3.2 or later) and PA-GAS
3909 (as available from jaguar.cs.utah.edu:/dist/pa-gas.u4.tar.Z).
3911 Many problems in the preliminary version have been fixed.
3913 * Faster and better demangling
3915 We have improved template demangling and fixed numerous bugs in the GNU style
3916 demangler. It can now handle type modifiers such as `static' or `const'. Wide
3917 character types (wchar_t) are now supported. Demangling of each symbol is now
3918 only done once, and is cached when the symbol table for a file is read in.
3919 This results in a small increase in memory usage for C programs, a moderate
3920 increase in memory usage for C++ programs, and a fantastic speedup in
3923 `Cfront' style demangling still doesn't work with AT&T cfront. It was written
3924 from the specifications in the Annotated Reference Manual, which AT&T's
3925 compiler does not actually implement.
3927 * G++ multiple inheritance compiler problem
3929 In the 2.3.2 release of gcc/g++, how the compiler resolves multiple
3930 inheritance lattices was reworked to properly discover ambiguities. We
3931 recently found an example which causes this new algorithm to fail in a
3932 very subtle way, producing bad debug information for those classes.
3933 The file 'gcc.patch' (in this directory) can be applied to gcc to
3934 circumvent the problem. A future GCC release will contain a complete
3937 The previous G++ debug info problem (mentioned below for the gdb-4.7
3938 release) is fixed in gcc version 2.3.2.
3940 * Improved configure script
3942 The `configure' script will now attempt to guess your system type if
3943 you don't supply a host system type. The old scheme of supplying a
3944 host system triplet is preferable over using this. All the magic is
3945 done in the new `config.guess' script. Examine it for details.
3947 We have also brought our configure script much more in line with the FSF's
3948 version. It now supports the --with-xxx options. In particular,
3949 `--with-minimal-bfd' can be used to make the GDB binary image smaller.
3950 The resulting GDB will not be able to read arbitrary object file formats --
3951 only the format ``expected'' to be used on the configured target system.
3952 We hope to make this the default in a future release.
3954 * Documentation improvements
3956 There's new internal documentation on how to modify GDB, and how to
3957 produce clean changes to the code. We implore people to read it
3958 before submitting changes.
3960 The GDB manual uses new, sexy Texinfo conditionals, rather than arcane
3961 M4 macros. The new texinfo.tex is provided in this release. Pre-built
3962 `info' files are also provided. To build `info' files from scratch,
3963 you will need the latest `makeinfo' release, which will be available in
3964 a future texinfo-X.Y release.
3966 *NOTE* The new texinfo.tex can cause old versions of TeX to hang.
3967 We're not sure exactly which versions have this problem, but it has
3968 been seen in 3.0. We highly recommend upgrading to TeX version 3.141
3969 or better. If that isn't possible, there is a patch in
3970 `texinfo/tex3patch' that will modify `texinfo/texinfo.tex' to work
3971 around this problem.
3975 GDB now supports array constants that can be used in expressions typed in by
3976 the user. The syntax is `{element, element, ...}'. Ie: you can now type
3977 `print {1, 2, 3}', and it will build up an array in memory malloc'd in
3980 The new directory `gdb/sparclite' contains a program that demonstrates
3981 how the sparc-stub.c remote stub runs on a Fujitsu SPARClite processor.
3983 * New native hosts supported
3985 HP/PA-RISC under HPUX using GNU tools hppa1.1-hp-hpux
3986 386 CPUs running SCO Unix 3.2v4 i386-unknown-sco3.2v4
3988 * New targets supported
3990 AMD 29k family via UDI a29k-amd-udi or udi29k
3992 * New file formats supported
3994 BFD now supports reading HP/PA-RISC executables (SOM file format?),
3995 HPUX core files, and SCO 3.2v2 core files.
3999 Attaching to processes now works again; thanks for the many bug reports.
4001 We have also stomped on a bunch of core dumps caused by
4002 printf_filtered("%s") problems.
4004 We eliminated a copyright problem on the rpc and ptrace header files
4005 for VxWorks, which was discovered at the last minute during the 4.7
4006 release. You should now be able to build a VxWorks GDB.
4008 You can now interrupt gdb while an attached process is running. This
4009 will cause the attached process to stop, and give control back to GDB.
4011 We fixed problems caused by using too many file descriptors
4012 for reading symbols from object files and libraries. This was
4013 especially a problem for programs that used many (~100) shared
4016 The `step' command now only enters a subroutine if there is line number
4017 information for the subroutine. Otherwise it acts like the `next'
4018 command. Previously, `step' would enter subroutines if there was
4019 any debugging information about the routine. This avoids problems
4020 when using `cc -g1' on MIPS machines.
4022 * Internal improvements
4024 GDB's internal interfaces have been improved to make it easier to support
4025 debugging of multiple languages in the future.
4027 GDB now uses a common structure for symbol information internally.
4028 Minimal symbols (derived from linkage symbols in object files), partial
4029 symbols (from a quick scan of debug information), and full symbols
4030 contain a common subset of information, making it easier to write
4031 shared code that handles any of them.
4033 * New command line options
4035 We now accept --silent as an alias for --quiet.
4039 The memory-mapped-malloc library is now licensed under the GNU Library
4040 General Public License.
4042 *** Changes in GDB-4.7:
4044 * Host/native/target split
4046 GDB has had some major internal surgery to untangle the support for
4047 hosts and remote targets. Now, when you configure GDB for a remote
4048 target, it will no longer load in all of the support for debugging
4049 local programs on the host. When fully completed and tested, this will
4050 ensure that arbitrary host/target combinations are possible.
4052 The primary conceptual shift is to separate the non-portable code in
4053 GDB into three categories. Host specific code is required any time GDB
4054 is compiled on that host, regardless of the target. Target specific
4055 code relates to the peculiarities of the target, but can be compiled on
4056 any host. Native specific code is everything else: it can only be
4057 built when the host and target are the same system. Child process
4058 handling and core file support are two common `native' examples.
4060 GDB's use of /proc for controlling Unix child processes is now cleaner.
4061 It has been split out into a single module under the `target_ops' vector,
4062 plus two native-dependent functions for each system that uses /proc.
4064 * New hosts supported
4066 HP/Apollo 68k (under the BSD domain) m68k-apollo-bsd or apollo68bsd
4067 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
4068 386 CPUs running SCO Unix i386-unknown-scosysv322 or i386sco
4070 * New targets supported
4072 Fujitsu SPARClite sparclite-fujitsu-none or sparclite
4073 68030 and CPU32 m68030-*-*, m68332-*-*
4075 * New native hosts supported
4077 386 CPUs running various BSD ports i386-unknown-bsd or 386bsd
4078 (386bsd is not well tested yet)
4079 386 CPUs running SCO Unix i386-unknown-scosysv322 or sco
4081 * New file formats supported
4083 BFD now supports COFF files for the Zilog Z8000 microprocessor. It
4084 supports reading of `a.out.adobe' object files, which are an a.out
4085 format extended with minimal information about multiple sections.
4089 `show copying' is the same as the old `info copying'.
4090 `show warranty' is the same as `info warrantee'.
4091 These were renamed for consistency. The old commands continue to work.
4093 `info handle' is a new alias for `info signals'.
4095 You can now define pre-command hooks, which attach arbitrary command
4096 scripts to any command. The commands in the hook will be executed
4097 prior to the user's command. You can also create a hook which will be
4098 executed whenever the program stops. See gdb.texinfo.
4102 We now deal with Cfront style name mangling, and can even extract type
4103 info from mangled symbols. GDB can automatically figure out which
4104 symbol mangling style your C++ compiler uses.
4106 Calling of methods and virtual functions has been improved as well.
4110 The crash that occured when debugging Sun Ansi-C compiled binaries is
4111 fixed. This was due to mishandling of the extra N_SO stabs output
4114 We also finally got Ultrix 4.2 running in house, and fixed core file
4115 support, with help from a dozen people on the net.
4117 John M. Farrell discovered that the reason that single-stepping was so
4118 slow on all of the Mips based platforms (primarily SGI and DEC) was
4119 that we were trying to demangle and lookup a symbol used for internal
4120 purposes on every instruction that was being stepped through. Changing
4121 the name of that symbol so that it couldn't be mistaken for a C++
4122 mangled symbol sped things up a great deal.
4124 Rich Pixley sped up symbol lookups in general by getting much smarter
4125 about when C++ symbol mangling is necessary. This should make symbol
4126 completion (TAB on the command line) much faster. It's not as fast as
4127 we'd like, but it's significantly faster than gdb-4.6.
4131 A new user controllable variable 'call_scratch_address' can
4132 specify the location of a scratch area to be used when GDB
4133 calls a function in the target. This is necessary because the
4134 usual method of putting the scratch area on the stack does not work
4135 in systems that have separate instruction and data spaces.
4137 We integrated changes to support the 29k UDI (Universal Debugger
4138 Interface), but discovered at the last minute that we didn't have all
4139 of the appropriate copyright paperwork. We are working with AMD to
4140 resolve this, and hope to have it available soon.
4144 We have sped up the remote serial line protocol, especially for targets
4145 with lots of registers. It now supports a new `expedited status' ('T')
4146 message which can be used in place of the existing 'S' status message.
4147 This allows the remote stub to send only the registers that GDB
4148 needs to make a quick decision about single-stepping or conditional
4149 breakpoints, eliminating the need to fetch the entire register set for
4150 each instruction being stepped through.
4152 The GDB remote serial protocol now implements a write-through cache for
4153 registers, only re-reading the registers if the target has run.
4155 There is also a new remote serial stub for SPARC processors. You can
4156 find it in gdb-4.7/gdb/sparc-stub.c. This was written to support the
4157 Fujitsu SPARClite processor, but will run on any stand-alone SPARC
4158 processor with a serial port.
4162 Configure.in files have become much easier to read and modify. A new
4163 `table driven' format makes it more obvious what configurations are
4164 supported, and what files each one uses.
4168 There is a new opcodes library which will eventually contain all of the
4169 disassembly routines and opcode tables. At present, it only contains
4170 Sparc and Z8000 routines. This will allow the assembler, debugger, and
4171 disassembler (binutils/objdump) to share these routines.
4173 The libiberty library is now copylefted under the GNU Library General
4174 Public License. This allows more liberal use, and was done so libg++
4175 can use it. This makes no difference to GDB, since the Library License
4176 grants all the rights from the General Public License.
4180 The file gdb-4.7/gdb/doc/stabs.texinfo is a (relatively) complete
4181 reference to the stabs symbol info used by the debugger. It is (as far
4182 as we know) the only published document on this fascinating topic. We
4183 encourage you to read it, compare it to the stabs information on your
4184 system, and send improvements on the document in general (to
4185 bug-gdb@prep.ai.mit.edu).
4187 And, of course, many bugs have been fixed.
4190 *** Changes in GDB-4.6:
4192 * Better support for C++ function names
4194 GDB now accepts as input the "demangled form" of C++ overloaded function
4195 names and member function names, and can do command completion on such names
4196 (using TAB, TAB-TAB, and ESC-?). The names have to be quoted with a pair of
4197 single quotes. Examples are 'func (int, long)' and 'obj::operator==(obj&)'.
4198 Make use of command completion, it is your friend.
4200 GDB also now accepts a variety of C++ mangled symbol formats. They are
4201 the GNU g++ style, the Cfront (ARM) style, and the Lucid (lcc) style.
4202 You can tell GDB which format to use by doing a 'set demangle-style {gnu,
4203 lucid, cfront, auto}'. 'gnu' is the default. Do a 'set demangle-style foo'
4204 for the list of formats.
4206 * G++ symbol mangling problem
4208 Recent versions of gcc have a bug in how they emit debugging information for
4209 C++ methods (when using dbx-style stabs). The file 'gcc.patch' (in this
4210 directory) can be applied to gcc to fix the problem. Alternatively, if you
4211 can't fix gcc, you can #define GCC_MANGLE_BUG when compling gdb/symtab.c. The
4212 usual symptom is difficulty with setting breakpoints on methods. GDB complains
4213 about the method being non-existent. (We believe that version 2.2.2 of GCC has
4216 * New 'maintenance' command
4218 All of the commands related to hacking GDB internals have been moved out of
4219 the main command set, and now live behind the 'maintenance' command. This
4220 can also be abbreviated as 'mt'. The following changes were made:
4222 dump-me -> maintenance dump-me
4223 info all-breakpoints -> maintenance info breakpoints
4224 printmsyms -> maintenance print msyms
4225 printobjfiles -> maintenance print objfiles
4226 printpsyms -> maintenance print psymbols
4227 printsyms -> maintenance print symbols
4229 The following commands are new:
4231 maintenance demangle Call internal GDB demangler routine to
4232 demangle a C++ link name and prints the result.
4233 maintenance print type Print a type chain for a given symbol
4235 * Change to .gdbinit file processing
4237 We now read the $HOME/.gdbinit file before processing the argv arguments
4238 (e.g. reading symbol files or core files). This allows global parameters to
4239 be set, which will apply during the symbol reading. The ./.gdbinit is still
4240 read after argv processing.
4242 * New hosts supported
4244 Solaris-2.0 !!! sparc-sun-solaris2 or sun4sol2
4246 GNU/Linux support i386-unknown-linux or linux
4248 We are also including code to support the HP/PA running BSD and HPUX. This
4249 is almost guaranteed not to work, as we didn't have time to test or build it
4250 for this release. We are including it so that the more adventurous (or
4251 masochistic) of you can play with it. We also had major problems with the
4252 fact that the compiler that we got from HP doesn't support the -g option.
4255 * New targets supported
4257 Hitachi H8/300 h8300-hitachi-hms or h8300hms
4259 * More smarts about finding #include files
4261 GDB now remembers the compilation directory for all include files, and for
4262 all files from which C is generated (like yacc and lex sources). This
4263 greatly improves GDB's ability to find yacc/lex sources, and include files,
4264 especially if you are debugging your program from a directory different from
4265 the one that contains your sources.
4267 We also fixed a bug which caused difficulty with listing and setting
4268 breakpoints in include files which contain C code. (In the past, you had to
4269 try twice in order to list an include file that you hadn't looked at before.)
4271 * Interesting infernals change
4273 GDB now deals with arbitrary numbers of sections, where the symbols for each
4274 section must be relocated relative to that section's landing place in the
4275 target's address space. This work was needed to support ELF with embedded
4276 stabs used by Solaris-2.0.
4278 * Bug fixes (of course!)
4280 There have been loads of fixes for the following things:
4281 mips, rs6000, 29k/udi, m68k, g++, type handling, elf/dwarf, m88k,
4282 i960, stabs, DOS(GO32), procfs, etc...
4284 See the ChangeLog for details.
4286 *** Changes in GDB-4.5:
4288 * New machines supported (host and target)
4290 IBM RS6000 running AIX rs6000-ibm-aix or rs6000
4292 SGI Irix-4.x mips-sgi-irix4 or iris4
4294 * New malloc package
4296 GDB now uses a new memory manager called mmalloc, based on gmalloc.
4297 Mmalloc is capable of handling mutiple heaps of memory. It is also
4298 capable of saving a heap to a file, and then mapping it back in later.
4299 This can be used to greatly speedup the startup of GDB by using a
4300 pre-parsed symbol table which lives in a mmalloc managed heap. For
4301 more details, please read mmalloc/mmalloc.texi.
4305 The 'info proc' command (SVR4 only) has been enhanced quite a bit. See
4306 'help info proc' for details.
4308 * MIPS ecoff symbol table format
4310 The code that reads MIPS symbol table format is now supported on all hosts.
4311 Thanks to MIPS for releasing the sym.h and symconst.h files to make this
4314 * File name changes for MS-DOS
4316 Many files in the config directories have been renamed to make it easier to
4317 support GDB on MS-DOSe systems (which have very restrictive file name
4318 conventions :-( ). MS-DOSe host support (under DJ Delorie's GO32
4319 environment) is close to working but has some remaining problems. Note
4320 that debugging of DOS programs is not supported, due to limitations
4321 in the ``operating system'', but it can be used to host cross-debugging.
4323 * Cross byte order fixes
4325 Many fixes have been made to support cross debugging of Sparc and MIPS
4326 targets from hosts whose byte order differs.
4328 * New -mapped and -readnow options
4330 If memory-mapped files are available on your system through the 'mmap'
4331 system call, you can use the -mapped option on the `file' or
4332 `symbol-file' commands to cause GDB to write the symbols from your
4333 program into a reusable file. If the program you are debugging is
4334 called `/path/fred', the mapped symbol file will be `./fred.syms'.
4335 Future GDB debugging sessions will notice the presence of this file,
4336 and will quickly map in symbol information from it, rather than reading
4337 the symbol table from the executable program. Using the '-mapped'
4338 option in a GDB `file' or `symbol-file' command has the same effect as
4339 starting GDB with the '-mapped' command-line option.
4341 You can cause GDB to read the entire symbol table immediately by using
4342 the '-readnow' option with any of the commands that load symbol table
4343 information (or on the GDB command line). This makes the command
4344 slower, but makes future operations faster.
4346 The -mapped and -readnow options are typically combined in order to
4347 build a `fred.syms' file that contains complete symbol information.
4348 A simple GDB invocation to do nothing but build a `.syms' file for future
4351 gdb -batch -nx -mapped -readnow programname
4353 The `.syms' file is specific to the host machine on which GDB is run.
4354 It holds an exact image of GDB's internal symbol table. It cannot be
4355 shared across multiple host platforms.
4357 * longjmp() handling
4359 GDB is now capable of stepping and nexting over longjmp(), _longjmp(), and
4360 siglongjmp() without losing control. This feature has not yet been ported to
4361 all systems. It currently works on many 386 platforms, all MIPS-based
4362 platforms (SGI, DECstation, etc), and Sun3/4.
4366 Preliminary work has been put in to support the new Solaris OS from Sun. At
4367 this time, it can control and debug processes, but it is not capable of
4372 As always, many many bug fixes. The major areas were with g++, and mipsread.
4373 People using the MIPS-based platforms should experience fewer mysterious
4374 crashes and trashed symbol tables.
4376 *** Changes in GDB-4.4:
4378 * New machines supported (host and target)
4380 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
4382 BSD Reno on Vax vax-dec-bsd
4383 Ultrix on Vax vax-dec-ultrix
4385 * New machines supported (target)
4387 AMD 29000 embedded, using EBMON a29k-none-none
4391 GDB continues to improve its handling of C++. `References' work better.
4392 The demangler has also been improved, and now deals with symbols mangled as
4393 per the Annotated C++ Reference Guide.
4395 GDB also now handles `stabs' symbol information embedded in MIPS
4396 `ecoff' symbol tables. Since the ecoff format was not easily
4397 extensible to handle new languages such as C++, this appeared to be a
4398 good way to put C++ debugging info into MIPS binaries. This option
4399 will be supported in the GNU C compiler, version 2, when it is
4402 * New features for SVR4
4404 GDB now handles SVR4 shared libraries, in the same fashion as SunOS
4405 shared libraries. Debugging dynamically linked programs should present
4406 only minor differences from debugging statically linked programs.
4408 The `info proc' command will print out information about any process
4409 on an SVR4 system (including the one you are debugging). At the moment,
4410 it prints the address mappings of the process.
4412 If you bring up GDB on another SVR4 system, please send mail to
4413 bug-gdb@prep.ai.mit.edu to let us know what changes were reqired (if any).
4415 * Better dynamic linking support in SunOS
4417 Reading symbols from shared libraries which contain debugging symbols
4418 now works properly. However, there remain issues such as automatic
4419 skipping of `transfer vector' code during function calls, which
4420 make it harder to debug code in a shared library, than to debug the
4421 same code linked statically.
4425 GDB is now using the latest `getopt' routines from the FSF. This
4426 version accepts the -- prefix for options with long names. GDB will
4427 continue to accept the old forms (-option and +option) as well.
4428 Various single letter abbreviations for options have been explicity
4429 added to the option table so that they won't get overshadowed in the
4430 future by other options that begin with the same letter.
4434 The `cleanup_undefined_types' bug that many of you noticed has been squashed.
4435 Many assorted bugs have been handled. Many more remain to be handled.
4436 See the various ChangeLog files (primarily in gdb and bfd) for details.
4439 *** Changes in GDB-4.3:
4441 * New machines supported (host and target)
4443 Amiga 3000 running Amix m68k-cbm-svr4 or amix
4444 NCR 3000 386 running SVR4 i386-ncr-svr4 or ncr3000
4445 Motorola Delta 88000 running Sys V m88k-motorola-sysv or delta88
4447 * Almost SCO Unix support
4449 We had hoped to support:
4450 SCO Unix on i386 IBM PC clones i386-sco-sysv or i386sco
4451 (except for core file support), but we discovered very late in the release
4452 that it has problems with process groups that render gdb unusable. Sorry
4453 about that. I encourage people to fix it and post the fixes.
4455 * Preliminary ELF and DWARF support
4457 GDB can read ELF object files on System V Release 4, and can handle
4458 debugging records for C, in DWARF format, in ELF files. This support
4459 is preliminary. If you bring up GDB on another SVR4 system, please
4460 send mail to bug-gdb@prep.ai.mit.edu to let us know what changes were
4465 GDB now uses the latest `readline' library. One user-visible change
4466 is that two tabs will list possible command completions, which previously
4467 required typing M-? (meta-question mark, or ESC ?).
4471 The `stepi' bug that many of you noticed has been squashed.
4472 Many bugs in C++ have been handled. Many more remain to be handled.
4473 See the various ChangeLog files (primarily in gdb and bfd) for details.
4475 * State of the MIPS world (in case you wondered):
4477 GDB can understand the symbol tables emitted by the compilers
4478 supplied by most vendors of MIPS-based machines, including DEC. These
4479 symbol tables are in a format that essentially nobody else uses.
4481 Some versions of gcc come with an assembler post-processor called
4482 mips-tfile. This program is required if you want to do source-level
4483 debugging of gcc-compiled programs. I believe FSF does not ship
4484 mips-tfile with gcc version 1, but it will eventually come with gcc
4487 Debugging of g++ output remains a problem. g++ version 1.xx does not
4488 really support it at all. (If you're lucky, you should be able to get
4489 line numbers and stack traces to work, but no parameters or local
4490 variables.) With some work it should be possible to improve the
4493 When gcc version 2 is released, you will have somewhat better luck.
4494 However, even then you will get confusing results for inheritance and
4497 We will eventually provide full debugging of g++ output on
4498 DECstations. This will probably involve some kind of stabs-in-ecoff
4499 encapulation, but the details have not been worked out yet.
4502 *** Changes in GDB-4.2:
4504 * Improved configuration
4506 Only one copy of `configure' exists now, and it is not self-modifying.
4507 Porting BFD is simpler.
4511 The `step' and `next' commands now only stop at the first instruction
4512 of a source line. This prevents the multiple stops that used to occur
4513 in switch statements, for-loops, etc. `Step' continues to stop if a
4514 function that has debugging information is called within the line.
4518 Lots of small bugs fixed. More remain.
4520 * New host supported (not target)
4522 Intel 386 PC clone running Mach i386-none-mach
4525 *** Changes in GDB-4.1:
4527 * Multiple source language support
4529 GDB now has internal scaffolding to handle several source languages.
4530 It determines the type of each source file from its filename extension,
4531 and will switch expression parsing and number formatting to match the
4532 language of the function in the currently selected stack frame.
4533 You can also specifically set the language to be used, with
4534 `set language c' or `set language modula-2'.
4538 GDB now has preliminary support for the GNU Modula-2 compiler,
4539 currently under development at the State University of New York at
4540 Buffalo. Development of both GDB and the GNU Modula-2 compiler will
4541 continue through the fall of 1991 and into 1992.
4543 Other Modula-2 compilers are currently not supported, and attempting to
4544 debug programs compiled with them will likely result in an error as the
4545 symbol table is read. Feel free to work on it, though!
4547 There are hooks in GDB for strict type checking and range checking,
4548 in the `Modula-2 philosophy', but they do not currently work.
4552 GDB can now write to executable and core files (e.g. patch
4553 a variable's value). You must turn this switch on, specify
4554 the file ("exec foo" or "core foo"), *then* modify it, e.g.
4555 by assigning a new value to a variable. Modifications take
4558 * Automatic SunOS shared library reading
4560 When you run your program, GDB automatically determines where its
4561 shared libraries (if any) have been loaded, and reads their symbols.
4562 The `share' command is no longer needed. This also works when
4563 examining core files.
4567 You can specify the number of lines that the `list' command shows.
4570 * New machines supported (host and target)
4572 SGI Iris (MIPS) running Irix V3: mips-sgi-irix or iris
4573 Sony NEWS (68K) running NEWSOS 3.x: m68k-sony-sysv or news
4574 Ultracomputer (29K) running Sym1: a29k-nyu-sym1 or ultra3
4576 * New hosts supported (not targets)
4578 IBM RT/PC: romp-ibm-aix or rtpc
4580 * New targets supported (not hosts)
4582 AMD 29000 embedded with COFF a29k-none-coff
4583 AMD 29000 embedded with a.out a29k-none-aout
4584 Ultracomputer remote kernel debug a29k-nyu-kern
4586 * New remote interfaces
4592 *** Changes in GDB-4.0:
4596 Wide output is wrapped at good places to make the output more readable.
4598 Gdb now supports cross-debugging from a host machine of one type to a
4599 target machine of another type. Communication with the target system
4600 is over serial lines. The ``target'' command handles connecting to the
4601 remote system; the ``load'' command will download a program into the
4602 remote system. Serial stubs for the m68k and i386 are provided. Gdb
4603 also supports debugging of realtime processes running under VxWorks,
4604 using SunRPC Remote Procedure Calls over TCP/IP to talk to a debugger
4605 stub on the target system.
4607 New CPUs supported include the AMD 29000 and Intel 960.
4609 GDB now reads object files and symbol tables via a ``binary file''
4610 library, which allows a single copy of GDB to debug programs of multiple
4611 object file types such as a.out and coff.
4613 There is now a GDB reference card in "doc/refcard.tex". (Make targets
4614 refcard.dvi and refcard.ps are available to format it).
4617 * Control-Variable user interface simplified
4619 All variables that control the operation of the debugger can be set
4620 by the ``set'' command, and displayed by the ``show'' command.
4622 For example, ``set prompt new-gdb=>'' will change your prompt to new-gdb=>.
4623 ``Show prompt'' produces the response:
4624 Gdb's prompt is new-gdb=>.
4626 What follows are the NEW set commands. The command ``help set'' will
4627 print a complete list of old and new set commands. ``help set FOO''
4628 will give a longer description of the variable FOO. ``show'' will show
4629 all of the variable descriptions and their current settings.
4631 confirm on/off: Enables warning questions for operations that are
4632 hard to recover from, e.g. rerunning the program while
4633 it is already running. Default is ON.
4635 editing on/off: Enables EMACS style command line editing
4636 of input. Previous lines can be recalled with
4637 control-P, the current line can be edited with control-B,
4638 you can search for commands with control-R, etc.
4641 history filename NAME: NAME is where the gdb command history
4642 will be stored. The default is .gdb_history,
4643 or the value of the environment variable
4646 history size N: The size, in commands, of the command history. The
4647 default is 256, or the value of the environment variable
4650 history save on/off: If this value is set to ON, the history file will
4651 be saved after exiting gdb. If set to OFF, the
4652 file will not be saved. The default is OFF.
4654 history expansion on/off: If this value is set to ON, then csh-like
4655 history expansion will be performed on
4656 command line input. The default is OFF.
4658 radix N: Sets the default radix for input and output. It can be set
4659 to 8, 10, or 16. Note that the argument to "radix" is interpreted
4660 in the current radix, so "set radix 10" is always a no-op.
4662 height N: This integer value is the number of lines on a page. Default
4663 is 24, the current `stty rows'' setting, or the ``li#''
4664 setting from the termcap entry matching the environment
4667 width N: This integer value is the number of characters on a line.
4668 Default is 80, the current `stty cols'' setting, or the ``co#''
4669 setting from the termcap entry matching the environment
4672 Note: ``set screensize'' is obsolete. Use ``set height'' and
4673 ``set width'' instead.
4675 print address on/off: Print memory addresses in various command displays,
4676 such as stack traces and structure values. Gdb looks
4677 more ``symbolic'' if you turn this off; it looks more
4678 ``machine level'' with it on. Default is ON.
4680 print array on/off: Prettyprint arrays. New convenient format! Default
4683 print demangle on/off: Print C++ symbols in "source" form if on,
4686 print asm-demangle on/off: Same, for assembler level printouts
4689 print vtbl on/off: Prettyprint C++ virtual function tables. Default is OFF.
4692 * Support for Epoch Environment.
4694 The epoch environment is a version of Emacs v18 with windowing. One
4695 new command, ``inspect'', is identical to ``print'', except that if you
4696 are running in the epoch environment, the value is printed in its own
4700 * Support for Shared Libraries
4702 GDB can now debug programs and core files that use SunOS shared libraries.
4703 Symbols from a shared library cannot be referenced
4704 before the shared library has been linked with the program (this
4705 happens after you type ``run'' and before the function main() is entered).
4706 At any time after this linking (including when examining core files
4707 from dynamically linked programs), gdb reads the symbols from each
4708 shared library when you type the ``sharedlibrary'' command.
4709 It can be abbreviated ``share''.
4711 sharedlibrary REGEXP: Load shared object library symbols for files
4712 matching a unix regular expression. No argument
4713 indicates to load symbols for all shared libraries.
4715 info sharedlibrary: Status of loaded shared libraries.
4720 A watchpoint stops execution of a program whenever the value of an
4721 expression changes. Checking for this slows down execution
4722 tremendously whenever you are in the scope of the expression, but is
4723 quite useful for catching tough ``bit-spreader'' or pointer misuse
4724 problems. Some machines such as the 386 have hardware for doing this
4725 more quickly, and future versions of gdb will use this hardware.
4727 watch EXP: Set a watchpoint (breakpoint) for an expression.
4729 info watchpoints: Information about your watchpoints.
4731 delete N: Deletes watchpoint number N (same as breakpoints).
4732 disable N: Temporarily turns off watchpoint number N (same as breakpoints).
4733 enable N: Re-enables watchpoint number N (same as breakpoints).
4736 * C++ multiple inheritance
4738 When used with a GCC version 2 compiler, GDB supports multiple inheritance
4741 * C++ exception handling
4743 Gdb now supports limited C++ exception handling. Besides the existing
4744 ability to breakpoint on an exception handler, gdb can breakpoint on
4745 the raising of an exception (before the stack is peeled back to the
4748 catch FOO: If there is a FOO exception handler in the dynamic scope,
4749 set a breakpoint to catch exceptions which may be raised there.
4750 Multiple exceptions (``catch foo bar baz'') may be caught.
4752 info catch: Lists all exceptions which may be caught in the
4753 current stack frame.
4756 * Minor command changes
4758 The command ``call func (arg, arg, ...)'' now acts like the print
4759 command, except it does not print or save a value if the function's result
4760 is void. This is similar to dbx usage.
4762 The ``up'' and ``down'' commands now always print the frame they end up
4763 at; ``up-silently'' and `down-silently'' can be used in scripts to change
4764 frames without printing.
4766 * New directory command
4768 'dir' now adds directories to the FRONT of the source search path.
4769 The path starts off empty. Source files that contain debug information
4770 about the directory in which they were compiled can be found even
4771 with an empty path; Sun CC and GCC include this information. If GDB can't
4772 find your source file in the current directory, type "dir .".
4774 * Configuring GDB for compilation
4776 For normal use, type ``./configure host''. See README or gdb.texinfo
4779 GDB now handles cross debugging. If you are remotely debugging between
4780 two different machines, type ``./configure host -target=targ''.
4781 Host is the machine where GDB will run; targ is the machine
4782 where the program that you are debugging will run.